@article{43194, abstract = {{For incident light polarized perpendicular to the tube axis the multi-band semiconductor Bloch equations (MB-SBEs) that involve various screened interband Coulomb interactions (ICIs) are derived. The calculated E 12 peak is very close to the longitudinal excitonic peak E 22. Compared with the previous theoretical peak positions, the blue-shift of the peak in our results is about 0.5 eV. Then, subsequent detailed analyses show that the screening effect on the diagonal ICIs (D-ICIs) plays a key role in this big blue-shift. The valley-degenerate transverse pair excitations holding the same selection rule further enhance the screening effect on D-ICIs. Specially at q = 0 the dielectric function acting on the D-ICIs enhances two times. In our calculation the strong screening effect contributes 90% of the big blue-shift, while the non-diagonal ICIs (ND-ICIs) contribute to 10% of the blue-shift.}}, author = {{Meier, Torsten and Liu, Hong}}, journal = {{The European Physical Journal B}}, title = {{{Influence of strong screening effect on the perpendicular polarized linear excitonic absorption spectra of semiconducting carbon nanotubes}}}, doi = {{10.1140/epjb/e2016-70476-8}}, volume = {{89}}, year = {{2016}}, } @article{13917, abstract = {{We present the synthesis of indium oxide (In2O3) inverse opal films with photonic stop bands in the visible range by a structure replication method. Artificial opal films made of poly(methyl methacrylate) (PMMA) spheres are utilized as template. The opal films are deposited via sedimentation facilitated by ultrasonication, and then impregnated by indium nitrate solution, which is thermally converted to In2O3 after drying. The quality of the resulting inverse opal film depends on many parameters; in this study the water content of the indium nitrate/PMMA composite after drying is investigated. Comparison of the reflectance spectra recorded by vis-spectroscopy with simulated data shows a good agreement between the peak position and calculated stop band positions for the inverse opals. This synthesis is less complex and highly efficient compared to most other techniques and is suitable for use in many applications.}}, author = {{Amrehn, Sabrina and Berghoff, Daniel and Nikitin, Andreas and Reichelt, Matthias and Wu, Xia and Meier, Torsten and Wagner, Thorsten}}, issn = {{1569-4410}}, journal = {{Photonics and Nanostructures - Fundamentals and Applications}}, pages = {{55--63}}, title = {{{Indium oxide inverse opal films synthesized by structure replication method}}}, doi = {{10.1016/j.photonics.2016.02.005}}, volume = {{19}}, year = {{2016}}, } @article{13915, abstract = {{The dynamics of a pair of harmonic oscillators represented by three-dimensional fields coupled with a repulsive cubic nonlinearity is investigated through direct simulations of the respective field equations and with the help of the finite-mode Galerkin approximation (GA), which represents the two interacting fields by a superposition of 3+3 harmonic-oscillator p-wave eigenfunctions with orbital and magnetic quantum numbers l=1 and m=1, 0, −1. The system can be implemented in binary Bose-Einstein condensates, demonstrating the potential of the atomic condensates to emulate various complex modes predicted by classical field theories. First, the GA very accurately predicts a broadly degenerate set of the system's ground states in the p-wave manifold, in the form of complexes built of a dipole coaxial with another dipole or vortex, as well as complexes built of mutually orthogonal dipoles. Next, pairs of noncoaxial vortices and/or dipoles, including pairs of mutually perpendicular vortices, develop remarkably stable dynamical regimes, which feature periodic exchange of the angular momentum and periodic switching between dipoles and vortices. For a moderately strong nonlinearity, simulations of the coupled-field equations agree very well with results produced by the GA, demonstrating that the dynamics is accurately spanned by the set of six modes limited to l=1.}}, author = {{Driben, R. and Konotop, V. V. and Malomed, B. A. and Meier, Torsten}}, issn = {{2470-0045}}, journal = {{Physical Review E}}, number = {{1}}, title = {{{Dynamics of dipoles and vortices in nonlinearly coupled three-dimensional field oscillators}}}, doi = {{10.1103/physreve.94.012207}}, volume = {{94}}, year = {{2016}}, } @inproceedings{13918, author = {{Podzimski, Reinold and Duc, Huynh Thanh and Priyadarshi, Shekhar and Schmidt, Christian and Bieler, Mark and Meier, Torsten}}, booktitle = {{Ultrafast Phenomena and Nanophotonics XX}}, editor = {{Betz, Markus and Elezzabi, Abdulhakem Y.}}, publisher = {{SPIE}}, title = {{{Photocurrents in semiconductors and semiconductor quantum wells analyzed by k.p-based Bloch equations}}}, doi = {{10.1117/12.2208572}}, volume = {{9746}}, year = {{2016}}, } @article{4246, abstract = {{Spins in semiconductor quantum dots have been considered as prospective quantum bit excitations. Their coupling to the crystal environment manifests itself in a limitation of the spin coherence times to the microsecond range, both for electron and hole spins. This rather short-lived coherence compared to atomic states asks for manipulations on timescales as short as possible. Due to the huge dipole moment for transitions between the valence and conduction band, pulsed laser systems offer the possibility to perform manipulations within picoseconds or even faster. Here, we report on results that show the potential of optical spin manipulations with currently available pulsed laser systems. Using picosecond laser pulses, we demonstrate optically induced spin rotations of electron and hole spins. We further realize the optical decoupling of the hole spins from the nuclear surrounding at the nanosecond timescales and demonstrate an all-optical spin tomography for interacting electron spin sub-ensembles.}}, author = {{Varwig, S. and Evers, E. and Greilich, A. and Yakovlev, D. R. and Reuter, Dirk and Wieck, A. D. and Meier, Torsten and Zrenner, Artur and Bayer, M.}}, issn = {{0946-2171}}, journal = {{Applied Physics B}}, keywords = {{Spin Polarization, Pump Pulse, Trion, Spin Component, Coherence Time}}, number = {{1}}, publisher = {{Springer Nature}}, title = {{{Advanced optical manipulation of carrier spins in (In,Ga)As quantum dots}}}, doi = {{10.1007/s00340-015-6274-y}}, volume = {{122}}, year = {{2016}}, } @article{13910, author = {{Ma, Xuekai and Driben, Rodislav and Malomed, Boris A. and Meier, Torsten and Schumacher, Stefan}}, issn = {{2045-2322}}, journal = {{Scientific Reports}}, title = {{{Two-dimensional symbiotic solitons and vortices in binary condensates with attractive cross-species interaction}}}, doi = {{10.1038/srep34847}}, volume = {{6}}, year = {{2016}}, } @article{43196, abstract = {{A method is presented to transfer a system of two-level atoms from a spin coherent state to a maximally spin squeezed Dicke state, relevant for quantum metrology and quantum information processing. The initial state is the ground state of an initial linear Hamiltonian that is gradually turned into a final quadratic Hamiltonian whose ground state is the selected Dicke state. We use compensating operators to suppress diabatic transitions to unwanted states that would occur if the change were not slow. We discuss the possibilities of constructing the compensating operators by sequential application of quadratic Hamiltonians available in experiments.}}, author = {{Meier, Torsten and Opatrný, T. and Saberi, H. and Brion, E. and Mølmer, K.}}, journal = {{Physical Review A}}, number = {{2}}, title = {{{Counterdiabatic driving in spin squeezing and Dicke-state preparation}}}, doi = {{10.1103/PhysRevA.93.023815}}, volume = {{93}}, year = {{2016}}, } @article{43195, abstract = {{We propose an entanglement classification for symmetric quantum states based on their diagonal matrix-product-state (MPS) representation. The proposed classification, which preserves the stochastic local operation assisted with classical communication (SLOCC) criterion, relates entanglement families to the interaction length of Hamiltonians. In this manner, we establish a connection between entanglement classification and condensed matter models from a quantum information perspective. Moreover, we introduce a scalable nesting property for the proposed entanglement classification, in which the families for N parties carry over to the N + 1 case. Finally, using techniques from algebraic geometry, we prove that the minimal nontrivial interaction length n for any symmetric state is bounded by .}}, author = {{Sanz, M. and Egusquiza, I.L. and Candia, R. Di and Saberi, H. and Lamata, L. and Solano, E.}}, journal = {{Scientific Reports}}, title = {{{Entanglement classification with matrix product states}}}, doi = {{10.1038/srep30188}}, volume = {{6}}, year = {{2016}}, } @article{22942, abstract = {{A microscopic approach that is based on the multisubband semiconductor Bloch equations formulated in the basis of a 14-band k⋅p model is employed to compute the temporal dynamics of photocurrents in GaAs quantum wells following excitation with femtosecond laser pulses. This approach provides a transparent description of the interband, intersubband, and intraband excitations, fully includes all resonant as well as off-resonant excitations, and treats the light-matter interaction nonperturbatively. For linearly polarized excitations, the photocurrents contain contributions from shift and rectification currents. We numerically compute and analyze these currents generated by excitation with femtosecond laser pulses for [110]- and [111]-oriented GaAs quantum wells. It is shown that the often employed perturbative χ(2) approach breaks down for peak fields larger than about 10 kV/cm, and that nonperturbative effects lead to a reduction of the peak values of the shift and rectification currents and to temporal oscillations that originate from Rabi flopping. In particular, we find a complex oscillatory photon energy dependence of the magnitudes of the shift and rectification currents. Our simulations demonstrate that this dependence is the result of mixing between the heavy- and light-hole valence bands. This is a surprising finding since the band mixing has an even larger influence on the strength of the photocurrents than the absorption coefficient. For [110]-oriented GaAs quantum wells, the calculated photon energy dependence is compared to experimental results, and good agreement is obtained. This validates our theoretical approach.}}, author = {{Duc, Huynh Thanh and Podzimski, Reinold and Priyadarshi, Shekhar and Bieler, Mark and Meier, Torsten}}, issn = {{2469-9950}}, journal = {{Physical Review B}}, number = {{8}}, publisher = {{American Physical Society}}, title = {{{Ultrafast shift and rectification photocurrents in GaAs quantum wells: Excitation intensity dependence and the importance of band mixing}}}, doi = {{10.1103/physrevb.94.085305}}, volume = {{94}}, year = {{2016}}, } @article{13916, abstract = {{Nonlinearity is the driving force for numerous important effects in nature typically showing transitions between different regimes, regular, chaotic or catastrophic behavior. Localized nonlinear modes have been the focus of intense research in areas such as fluid and gas dynamics, photonics, atomic and solid state physics etc. Due to the richness of the behavior of nonlinear systems and due to the severe numerical demands of accurate three-dimensional (3D) numerical simulations presently only little knowledge is available on the dynamics of complex nonlinear modes in 3D. Here, we investigate the dynamics of 3D non-coaxial matter wave vortices that are trapped in a parabolic potential and interact via a repulsive nonlinearity. Our numerical simulations demonstrate the existence of an unexpected and fascinating nonlinear regime that starts immediately when the nonlinearity is switched-on and is characterized by a smooth dynamics representing torque-free precession with nutations. The reported motion is proven to be robust regarding various effects such as the number of particles, dissipation and trap deformations and thus should be observable in suitably designed experiments. Since our theoretical approach, i.e., coupled nonlinear Schrödinger equations, is quite generic, we expect that the obtained novel dynamical behavior should also exist in other nonlinear systems.}}, author = {{Driben, R. and Konotop, V. V. and Meier, Torsten}}, issn = {{2045-2322}}, journal = {{Scientific Reports}}, title = {{{Precession and nutation dynamics of nonlinearly coupled non-coaxial three-dimensional matter wave vortices}}}, doi = {{10.1038/srep22758}}, volume = {{6}}, year = {{2016}}, } @article{13920, abstract = {{We investigate the transient optical response in high-quality Cd0.88Zn0.12Te crystals in the regime of slow light propagation on the lower exciton-polariton branch. Femtosecond photoexcitation leads to very substantial transmission changes in a ∼10-meV broad spectral range within the transparency window of the unexcited semiconductor. These nonlinear optical signatures decay on picosecond time scales governed by carrier thermalization and recombination. The temporal and spectral dependence indicate the dynamical optical response as arising from excitation-induced dephasing and perturbed free induction decay. Model simulations for the optical response taking into account the actual exciton-polariton dispersion and excitation-induced dephasing of a nonlinearly driven two-level system support this interpretation.}}, author = {{Lohrenz, J. and Melzer, S. and Ruppert, C. and Akimov, I. A. and Mariette, H. and Reichelt, Matthias and Trautmann, Alexander and Meier, Torsten and Betz, M.}}, issn = {{2469-9950}}, journal = {{Physical Review B}}, number = {{7}}, title = {{{Ultrafast dynamical response of the lower exciton-polariton branch in CdZnTe}}}, doi = {{10.1103/physrevb.93.075201}}, volume = {{93}}, year = {{2016}}, } @article{13923, author = {{Oreshnikov, I. and Driben, R. and Yulin, A. V.}}, issn = {{0146-9592}}, journal = {{Optics Letters}}, number = {{23}}, title = {{{Interaction of high-order solitons with external dispersive waves}}}, doi = {{10.1364/ol.40.005554}}, volume = {{40}}, year = {{2015}}, } @article{13924, author = {{Oreshnikov, I. and Driben, R. and Yulin, A. V.}}, issn = {{0146-9592}}, journal = {{Optics Letters}}, number = {{21}}, title = {{{Weak and strong interactions between dark solitons and dispersive waves}}}, doi = {{10.1364/ol.40.004871}}, volume = {{40}}, year = {{2015}}, } @article{13925, author = {{Driben, R. and Yulin, A. V. and Efimov, A.}}, issn = {{1094-4087}}, journal = {{Optics Express}}, number = {{15}}, title = {{{Resonant radiation from oscillating higher order solitons}}}, doi = {{10.1364/oe.23.019112}}, volume = {{23}}, year = {{2015}}, } @article{13929, author = {{Oreshnikov, I. and Driben, R. and Yulin, A. V.}}, issn = {{0146-9592}}, journal = {{Optics Letters}}, number = {{23}}, title = {{{Interaction of high-order solitons with external dispersive waves}}}, doi = {{10.1364/ol.40.005554}}, volume = {{40}}, year = {{2015}}, } @article{13930, author = {{Oreshnikov, I. and Driben, R. and Yulin, A. V.}}, issn = {{0146-9592}}, journal = {{Optics Letters}}, number = {{21}}, title = {{{Weak and strong interactions between dark solitons and dispersive waves}}}, doi = {{10.1364/ol.40.004871}}, volume = {{40}}, year = {{2015}}, } @article{13931, author = {{Driben, R. and Yulin, A. V. and Efimov, A.}}, issn = {{1094-4087}}, journal = {{Optics Express}}, number = {{15}}, title = {{{Resonant radiation from oscillating higher order solitons}}}, doi = {{10.1364/oe.23.019112}}, volume = {{23}}, year = {{2015}}, } @article{43250, abstract = {{We present radiation mechanism exhibited by a higher order soliton. In a course of its evolution the higher-order soliton emits polychromatic radiation resulting in formation of multipeak frequency comb-like spectral band. The shape and spectral position of this band can be effectively controlled by the relative strength of the third order dispersion. An analytical description is corroborated by numerical simulations. It is shown that for longer pulses the described effect persists also under the action of higher order perturbations such as Raman and self-steepening.}}, author = {{Driben, R. and Yulin, A. V. and Efimov, A.}}, journal = {{Optics Express}}, number = {{15}}, pages = {{19112--19117}}, title = {{{Resonant radiation from oscillating higher order solitons}}}, doi = {{10.1364/OE.23.019112}}, volume = {{23}}, year = {{2015}}, } @article{43249, abstract = {{The effect of mutual interactions between dark solitons and dispersive waves is investigated numerically and analytically. The condition of the resonant scattering of dispersive waves on dark solitons is derived and compared against the results of the numerical simulations. It is shown that the interaction with intense dispersive waves affects the dynamics of the solitons by accelerating, decelerating, or destroying them. It is also demonstrated that two dark solitons can form a cavity for dispersive waves bouncing between the two dark solitons. The differences of the resonant scattering of the dispersive waves on dark and bright solitons are discussed. In particular, we demonstrate that two dark solitons and a dispersive wave bouncing in between them create a solitonic cavity with convex “mirrors,” unlike the concave “mirror” in the case of bright solitons.}}, author = {{Oreshnikov, I. and Yulin, A. V. and Driben, R.}}, journal = {{Optics Letters}}, number = {{21}}, pages = {{4871--4874}}, title = {{{Weak and strong interactions between dark solitons and dispersive waves}}}, doi = {{10.1364/OL.40.004871}}, volume = {{40}}, year = {{2015}}, } @inproceedings{43892, abstract = {{The discovery of Airy waves, in the context of solutions to the linear Schrödinger equation [1], inspired extensive research for self-accelerating waves in optical settings [2-6]. Fascinating self-accelerating, self-healing light beams propagating along the bending trajectories can manifest themself in the spatial and the temporal domains and are promising for a large variety of potential applications.}}, author = {{Meier, Torsten and Driben, R. and Konotop, V.V.}}, booktitle = {{European Conference on Lasers and Electro-Optics - European Quantum Electronics Conference}}, isbn = {{978-1-4673-7475-0}}, location = {{Munich, Germany}}, publisher = {{IEEE}}, title = {{{Vectorial self-accelerating beams}}}, year = {{2015}}, } @article{13935, abstract = {{Recently, a new class of nonlinear systems was introduced, in which the self-trapping of fundamental and vortical localized modes in space of dimension D is supported by cubic self-repulsion with a strength growing as a function of the distance from the center, r, at any rate faster that rD. These systems support robust 2D and 3D modes which either do not exist or are unstable in other nonlinear systems. Here we demonstrate a possibility to create solitary vortices in this setting by applying a phase-imprinting torque to the ground state. Initially, a strong torque completely destroys the ground state. However, contrary to usual systems, where the destruction is irreversible, the present ones demonstrate a rapid restabilization and the creation of one or several shifted vortices orbiting the center. For the sake of comparison, we show analytically that, in the linear system with a 3D trapping potential, the action of a torque on the ground state is inefficient and creates only even-vorticity states with a small probability.}}, author = {{Driben, Rodislav and Meier, Torsten and Malomed, Boris A.}}, issn = {{2045-2322}}, journal = {{Scientific Reports}}, title = {{{Creation of vortices by torque in multidimensional media with inhomogeneous defocusing nonlinearity}}}, doi = {{10.1038/srep09420}}, volume = {{5}}, year = {{2015}}, } @article{22944, abstract = {{Recently, a new class of nonlinear systems was introduced, in which the self-trapping of fundamental and vortical localized modes in space of dimension D is supported by cubic self-repulsion with a strength growing as a function of the distance from the center, r, at any rate faster that rD. These systems support robust 2D and 3D modes which either do not exist or are unstable in other nonlinear systems. Here we demonstrate a possibility to create solitary vortices in this setting by applying a phase-imprinting torque to the ground state. Initially, a strong torque completely destroys the ground state. However, contrary to usual systems, where the destruction is irreversible, the present ones demonstrate a rapid restabilization and the creation of one or several shifted vortices orbiting the center. For the sake of comparison, we show analytically that, in the linear system with a 3D trapping potential, the action of a torque on the ground state is inefficient and creates only even-vorticity states with a small probability.}}, author = {{Driben, Rodislav and Meier, Torsten and Malomed, Boris A.}}, issn = {{2045-2322}}, journal = {{Scientific Reports}}, title = {{{Creation of vortices by torque in multidimensional media with inhomogeneous defocusing nonlinearity}}}, doi = {{10.1038/srep09420}}, volume = {{5}}, year = {{2015}}, } @article{43896, abstract = {{It is demonstrated that a two-component Bose-Einstein condensate (BEC) with all-repulsive inter-atomic interactions loaded into a radially symmetric harmonic trap supports robust non-coaxial vortices with approximately orthogonal vortex lines in each of the components. These cross vortices are excited from the linear modes by a sudden switch-on of the nonlinearity (via Feshbach resonance) and are characterized by persistent dynamical regimes of precession with nutation, resembling the motion of a rigid body. The obtained dynamics can be understood qualitatively on the basis of a simple mechanical model.}}, author = {{Meier, Torsten and Driben, R. and Konotop, V.V.}}, journal = {{arXiv preprint arXiv:1505.04113}}, title = {{{Non-coaxial vortices in two-component Bose-Einstein condensates: Persistent precession and nutation}}}, doi = {{10.48550/arXiv.1505.04113}}, year = {{2015}}, } @article{13922, author = {{Liu, Hong and Heinze, Dirk Florian and Thanh Duc, Huynh and Schumacher, Stefan and Meier, Torsten}}, issn = {{0953-8984}}, journal = {{Journal of Physics: Condensed Matter}}, number = {{44}}, title = {{{Curvature effects in the band structure of carbon nanotubes including spin–orbit coupling}}}, doi = {{10.1088/0953-8984/27/44/445501}}, volume = {{27}}, year = {{2015}}, } @article{22946, abstract = {{The Kane–Mele model was previously used to describe effective spin–orbit couplings (SOCs) in graphene. Here we extend this model and also incorporate curvature effects to analyze the combined influence of SOC and curvature on the band structure of carbon nanotubes (CNTs). The extended model then reproduces the chirality-dependent asymmetric electron-hole splitting for semiconducting CNTs and in the band structure for metallic CNTs shows an opening of the band gap and a change of the Fermi wave vector with spin. For chiral semiconducting CNTs with large chiral angle we show that the spin-splitting configuration of bands near the Fermi energy depends on the value of $\text{mod}(2n+m,3)$ .}}, author = {{Liu, Hong and Heinze, Dirk Florian and Thanh Duc, Huynh and Schumacher, Stefan and Meier, Torsten}}, issn = {{0953-8984}}, journal = {{Journal of Physics: Condensed Matter}}, number = {{44}}, title = {{{Curvature effects in the band structure of carbon nanotubes including spin–orbit coupling}}}, doi = {{10.1088/0953-8984/27/44/445501}}, volume = {{27}}, year = {{2015}}, } @article{13926, abstract = {{We predict a variety of composite quiescent and spinning two- and three-dimensional (2D and 3D) self-trapped modes in media with a repulsive nonlinearity whose local strength grows from center to periphery. These are 2D dipoles and quadrupoles, and 3D octupoles, as well as vortex–antivortex pairs and quadruplets. Unlike other multidimensional models, where such complex bound states either do not exist or are subject to strong instabilities, these modes are remarkably robust in the present setting. The results are obtained by means of numerical methods and analytically, using the Thomas–Fermi approximation. The predicted states may be realized in optical and matter-wave media with controllable cubic nonlinearities}}, author = {{Driben, Rodislav and Dror, Nir and Malomed, Boris A and Meier, Torsten}}, issn = {{1367-2630}}, journal = {{New Journal of Physics}}, title = {{{Multipoles and vortex multiplets in multidimensional media with inhomogeneous defocusing nonlinearity}}}, doi = {{10.1088/1367-2630/17/8/083043}}, volume = {{17}}, year = {{2015}}, } @article{13932, abstract = {{We predict a variety of composite quiescent and spinning two- and three-dimensional (2D and 3D) self-trapped modes in media with a repulsive nonlinearity whose local strength grows from center to periphery. These are 2D dipoles and quadrupoles, and 3D octupoles, as well as vortex–antivortex pairs and quadruplets. Unlike other multidimensional models, where such complex bound states either do not exist or are subject to strong instabilities, these modes are remarkably robust in the present setting. The results are obtained by means of numerical methods and analytically, using the Thomas–Fermi approximation. The predicted states may be realized in optical and matter-wave media with controllable cubic nonlinearities}}, author = {{Driben, Rodislav and Dror, Nir and Malomed, Boris A and Meier, Torsten}}, issn = {{1367-2630}}, journal = {{New Journal of Physics}}, title = {{{Multipoles and vortex multiplets in multidimensional media with inhomogeneous defocusing nonlinearity}}}, doi = {{10.1088/1367-2630/17/8/083043}}, volume = {{17}}, year = {{2015}}, } @article{22948, abstract = {{We predict a variety of composite quiescent and spinning two- and three-dimensional (2D and 3D) self-trapped modes in media with a repulsive nonlinearity whose local strength grows from center to periphery. These are 2D dipoles and quadrupoles, and 3D octupoles, as well as vortex–antivortex pairs and quadruplets. Unlike other multidimensional models, where such complex bound states either do not exist or are subject to strong instabilities, these modes are remarkably robust in the present setting. The results are obtained by means of numerical methods and analytically, using the Thomas–Fermi approximation. The predicted states may be realized in optical and matter-wave media with controllable cubic nonlinearities}}, author = {{Driben, Rodislav and Dror, Nir and Malomed, Boris A. and Meier, Torsten}}, issn = {{1367-2630}}, journal = {{New Journal of Physics}}, title = {{{Multipoles and vortex multiplets in multidimensional media with inhomogeneous defocusing nonlinearity}}}, doi = {{10.1088/1367-2630/17/8/083043}}, volume = {{17}}, year = {{2015}}, } @inproceedings{13927, author = {{Lange, C. and Schubert, O. and Hohenleutner, M. and Langer, F. and Baierl, S. and Maag, T. and Urbanek, B. and Edwards, E. R. J. and Woltersdorf, G. and Bougeard, D. and Huttner, U. and Golde, D. and Meier, Torsten and Kira, M. and Koch, S. W. and Huber, R.}}, booktitle = {{Nonlinear Frequency Generation and Conversion: Materials, Devices, and Applications XIV}}, editor = {{Vodopyanov, Konstantin L.}}, publisher = {{SPIE}}, title = {{{Sub-cycle control of multi-THz high-harmonic generation and all-coherent charge transport in bulk semiconductors}}}, doi = {{10.1117/12.2085101}}, volume = {{9347}}, year = {{2015}}, } @inproceedings{13933, author = {{Lange, C. and Schubert, O. and Hohenleutner, M. and Langer, F. and Baierl, S. and Maag, T. and Urbanek, B. and Edwards, E. R. J. and Woltersdorf, G. and Bougeard, D. and Huttner, U. and Golde, D. and Meier, Torsten and Kira, M. and Koch, S. W. and Huber, R.}}, booktitle = {{Nonlinear Frequency Generation and Conversion: Materials, Devices, and Applications XIV}}, editor = {{Vodopyanov, Konstantin L.}}, publisher = {{SPIE}}, title = {{{Sub-cycle control of multi-THz high-harmonic generation and all-coherent charge transport in bulk semiconductors}}}, doi = {{10.1117/12.2085101}}, volume = {{9347}}, year = {{2015}}, } @inproceedings{22949, author = {{Lange, C. and Schubert, O. and Hohenleutner, M. and Langer, F. and Baierl, S. and Maag, T. and Urbanek, B. and Edwards, E. R. J. and Woltersdorf, G. and Bougeard, D. and Huttner, U. and Golde, D. and Meier, Torsten and Kira, M. and Koch, S. W. and Huber, R.}}, booktitle = {{Nonlinear Frequency Generation and Conversion: Materials, Devices, and Applications XIV}}, editor = {{Vodopyanov, Konstantin L.}}, publisher = {{SPIE}}, title = {{{Sub-cycle control of multi-THz high-harmonic generation and all-coherent charge transport in bulk semiconductors}}}, doi = {{10.1117/12.2085101}}, volume = {{9347}}, year = {{2015}}, } @inproceedings{22950, author = {{Podzimski, Reinold and Duc, Huynh T. and Meier, Torsten}}, booktitle = {{SPIE Proceedings Vol. 9361: Ultrafast Phenomena and Nanophotonics XIX}}, editor = {{Betz, Markus and Elezzabi, Abdulhakem Y. and Tsen, Kong-Thon}}, publisher = {{SPIE}}, title = {{{Time-domain calculations of shift currents in bulk GaAs}}}, doi = {{10.1117/12.2078123}}, volume = {{9361}}, year = {{2015}}, } @inproceedings{13934, author = {{Podzimski, Reinold and Duc, Huynh T. and Meier, Torsten}}, booktitle = {{Ultrafast Phenomena and Nanophotonics XIX}}, editor = {{Betz, Markus and Elezzabi, Abdulhakem Y. and Tsen, Kong-Thon}}, publisher = {{SPIE}}, title = {{{Time-domain calculations of shift currents in bulk GaAs}}}, doi = {{10.1117/12.2078123}}, volume = {{9361}}, year = {{2015}}, } @inproceedings{13928, author = {{Podzimski, Reinold and Duc, Huynh T. and Meier, Torsten}}, booktitle = {{Ultrafast Phenomena and Nanophotonics XIX}}, editor = {{Betz, Markus and Elezzabi, Abdulhakem Y. and Tsen, Kong-Thon}}, publisher = {{SPIE}}, title = {{{Time-domain calculations of shift currents in bulk GaAs}}}, doi = {{10.1117/12.2078123}}, volume = {{9361}}, year = {{2015}}, } @inproceedings{22945, author = {{Podzimski, Reinold and Duc, Huynh T. and Meier, Torsten}}, booktitle = {{Ultrafast Phenomena and Nanophotonics XIX}}, editor = {{Betz, Markus and Elezzabi, Abdulhakem Y. and Tsen, Kong-Thon}}, publisher = {{SPIE}}, title = {{{Time-domain calculations of shift currents in bulk GaAs}}}, doi = {{10.1117/12.2078123}}, volume = {{9361}}, year = {{2015}}, } @article{22947, author = {{Oreshnikov, I. and Driben, R. and Yulin, A. V.}}, issn = {{0146-9592}}, journal = {{Optics Letters}}, title = {{{Interaction of high-order solitons with external dispersive waves}}}, doi = {{10.1364/ol.40.005554}}, year = {{2015}}, } @article{43197, abstract = {{The effect of mutual interaction between second-order soliton and dispersive waves (DWs) is investigated. It is predicted analytically and confirmed numerically that DWs (both transmitted and reflected components) become polychromatic after interaction with the soliton. Collision with DWs of considerable intensity can lead to acceleration/deceleration and central frequency shift of the soliton, while still preserving the soliton’s oscillating structure. Two second-order solitons with resonant DWs trapped between them can form an effective solitonic cavity with “flat” or “concave mirrors,” depending on the intensity of the input.}}, author = {{Meier, Torsten and Oreshnikov, I. and Driben, R. and Yulin, A.V.}}, journal = {{Optics Letters}}, number = {{23}}, pages = {{5554--5557}}, title = {{{Interaction of high-order solitons with external dispersive waves}}}, doi = {{10.1364/OL.40.005554}}, volume = {{40}}, year = {{2015}}, } @article{43198, abstract = {{Ultrafast charge transport in strongly biased semiconductors is at the heart of high-speed electronics, electro-optics and fundamental solid-state physics1,2,3,4,5,6,7,8,9,10,11,12,13. Intense light pulses in the terahertz spectral range have opened fascinating vistas14,15,16,17,18,19,20,21. Because terahertz photon energies are far below typical electronic interband resonances, a stable electromagnetic waveform may serve as a precisely adjustable bias5,11,17,19. Novel quantum phenomena have been anticipated for terahertz amplitudes, reaching atomic field strengths8,9,10. We exploit controlled (multi-)terahertz waveforms with peak fields of 72 MV cm−1 to drive coherent interband polarization combined with dynamical Bloch oscillations in semiconducting gallium selenide. These dynamics entail the emission of phase-stable high-harmonic transients, covering the entire terahertz-to-visible spectral domain between 0.1 and 675 THz. Quantum interference of different ionization paths of accelerated charge carriers is controlled via the waveform of the driving field and explained by a quantum theory of inter- and intraband dynamics. Our results pave the way towards all-coherent terahertz-rate electronics.}}, author = {{Meier, Torsten and Schubert, O. and Hohenleutner, M. and Langer, F. and Urbanek, B. and Lange, C. and Huttner, U. and Golde, D. and Kira, M. and Koch, S. W. and Huber, R.}}, journal = {{Nature Photonics}}, number = {{2}}, publisher = {{Nature Publishing Group}}, title = {{{Sub-cycle control of terahertz high-harmonic generation by dynamical Bloch oscillations}}}, doi = {{10.1038/nphoton.2013.349}}, volume = {{8}}, year = {{2014}}, } @article{43251, abstract = {{The nonadiabatic dynamics of a many-body system driven through a quantum critical point can be controlled using counterdiabatic driving, where the formation of excitations is suppressed by assisting the dynamics with auxiliary multiple-body nonlocal interactions. We propose an alternative scheme which circumvents practical challenges to realize shortcuts to adiabaticity in mesoscopic systems by tailoring the functional form of the auxiliary counterdiabatic interactions. A driving scheme resorting in short-range few-body interactions is shown to generate an effectively adiabatic dynamics.}}, author = {{Saberi, H. and Opatrný, T. and Mølmer, K. and del Campo,, A.}}, journal = {{Physical Review A}}, number = {{6}}, title = {{{Adiabatic tracking of quantum many-body dynamics}}}, doi = {{10.1103/PhysRevA.90.060301}}, volume = {{90}}, year = {{2014}}, } @inproceedings{43907, abstract = {{The carrier wave of high-intensity phase-locked multi-THz pulses controls dynamical Bloch oscillations and interband polarization in bulk semiconductors, leading to the emission of all-coherent high-order harmonics covering 12.7 optical octaves from THz to VIS regimes.}}, author = {{Meier, Torsten}}, booktitle = {{Frontiers in Optics 2014, OSA Technical Digest}}, isbn = {{1-55752-286-3}}, location = {{Tucson, Arizona United States}}, title = {{{Coherent bloch oscillations driven by ultrastrong THz excitation}}}, doi = {{10.1364/LS.2014.LTu4I.2}}, year = {{2014}}, } @inproceedings{43920, abstract = {{Dynamical Bloch oscillations and coherent interband polarization in bulk GaSe are controlled by CEP-stable, ultra-intense multi-THz waveforms and result in the emission of phase-stable high-order harmonics covering 12.7 optical octaves from THz to VIS regimes.}}, author = {{Meier, Torsten and Langer, F. and Schubert, O. and Hohenleutner, M. and Urbanek, B. and Lange, C. and Huttner, U. and Golde, D. and Kira, M. and Koch, S.W. and Huber, R.}}, booktitle = {{CLEO: QELS_Fundamental Science}}, isbn = {{978-1-55752-999-2}}, location = {{San Jose, California United States}}, title = {{{CEP control of dynamical Bloch oscillations in a bulk semiconductor via ultra-intense multi-THz fields}}}, doi = {{10.1364/CLEO_QELS.2014.FTh1C.1}}, year = {{2014}}, } @article{22957, abstract = {{We show, by means of numerical and analytical methods, that media with a repulsive nonlinearity which grows from the center to the periphery support a remarkable variety of previously unknown complex stationary and dynamical three-dimensional (3D) solitary-wave states. Peanut-shaped modulation profiles give rise to vertically symmetric and antisymmetric vortex states, and novel stationary hybrid states, built of top and bottom vortices with opposite topological charges, as well as robust dynamical hybrids, which feature stable precession of a vortex on top of a zero-vorticity soliton. The analysis reveals stability regions for symmetric, antisymmetric, and hybrid states. In addition, bead-shaped modulation profiles give rise to the first example of exact analytical solutions for stable 3D vortex solitons. The predicted states may be realized in media with a controllable cubic nonlinearity, such as Bose–Einstein condensates.}}, author = {{Driben, Rodislav and Kartashov, Yaroslav V. and Malomed, Boris A. and Meier, Torsten and Torner, Lluis}}, issn = {{1367-2630}}, journal = {{New Journal of Physics}}, title = {{{Three-dimensional hybrid vortex solitons}}}, doi = {{10.1088/1367-2630/16/6/063035}}, volume = {{16}}, year = {{2014}}, } @article{43199, abstract = {{We find that the recently introduced model of self-trapping supported by a spatially growing strength of a repulsive nonlinearity gives rise to robust vortex-soliton tori, i.e., three-dimensional vortex solitons, with topological charges S≥1. The family with S=1 is completely stable, while the one with S=2 has alternating regions of stability and instability. The families are nearly exactly reproduced in an analytical form by the Thomas-Fermi approximation. Unstable states with S=2 and 3 split into persistently rotating pairs or triangles of unitary vortices. Application of a moderate torque to the vortex torus initiates a persistent precession mode, with the torus’ axle moving along a conical surface. A strong torque heavily deforms the vortex solitons, but, nonetheless, they restore themselves with the axle oriented according to the vectorial addition of angular momenta.}}, author = {{Meier, Torsten and Driben, R. and Kartashov, Y. V. and Malomed, B. A. and Torner, L.}}, journal = {{Physical review letters}}, number = {{2}}, title = {{{Soliton gyroscopes in media with spatially growing repulsive nonlinearity}}}, doi = {{10.1103/PhysRevLett.112.020404}}, volume = {{112}}, year = {{2014}}, } @article{22956, abstract = {{Parametric down-conversion (PDC) forms one of the basic building blocks for quantum optical experiments. However, the intrinsic multimode spectral-temporal structure of pulsed PDC often poses a severe hindrance for the direct implementation of the heralding of pure single-photon states or, for example, continuous-variable entanglement distillation experiments. To get rid of multimode effects narrowband frequency filtering is frequently applied to achieve a single-mode behavior. A rigorous theoretical description to accurately describe the effects of filtering on PDC, however, is still missing. To date, the theoretical models of filtered PDC are rooted in the discrete-variable domain and only account for filtering in the low-gain regime, where only a few photon pairs are emitted at any single point in time. In this paper we extend these theoretical descriptions and put forward a simple model, which is able to accurately describe the effects of filtering on PDC in the continuous-variable domain. This developed straightforward theoretical framework enables us to accurately quantify the tradeoff between suppression of higher-order modes, reduced purity, and lowered Einstein–Podolsky–Rosen entanglement, when narrowband filters are applied to multimode type-II PDC.}}, author = {{Christ, Andreas and Lupo, Cosmo and Reichelt, Matthias and Meier, Torsten and Silberhorn, Christine}}, issn = {{1050-2947}}, journal = {{Physical Review A}}, number = {{2}}, title = {{{Theory of filtered type-II parametric down-conversion in the continuous-variable domain: Quantifying the impacts of filtering}}}, doi = {{10.1103/physreva.90.023823}}, volume = {{90}}, year = {{2014}}, } @inproceedings{43914, abstract = {{Ultra-intense and CEP-stable waveforms in the multi-THz range control dynamical Bloch oscillations and interband polarization in bulk GaSe, leading to the emission of all-coherent high-order harmonics covering 12.7 optical octaves from THz to VIS regimes.}}, author = {{Meier, Torsten and Hohenleutner, M. and Schubert, O. and Langer, F. and Urbanek, B. and Lange, C. and Huttner, U. and Golde, D. and Kira, M. and Koch, S.W. and Huber, R.}}, booktitle = {{19th International Conference on Ultrafast Phenomena}}, isbn = {{1-55752-279-0}}, location = {{Okinawa Japan}}, title = {{{Phase-locked multi-THz high-harmonic generation by dynamical bloch oscillations in bulk semiconductors}}}, doi = {{10.1364/UP.2014.10.Thu.A.3}}, year = {{2014}}, } @article{22955, abstract = {{The dynamics of 3D Airy-vortex wave packets is studied under the action of strong self-focusing Kerr nonlinearity. Emissions of nonlinear 3D waves out of the main wave packets with the topological charges were demonstrated. Because of the conservation of the total angular momentum, charges of the emitted waves are equal to those carried by the parental light structure. The rapid collapse imposes a severe limitation on the propagation of multidimensional waves in Kerr media. However, the structure of the Airy beam carrier allows the coupling of light from the leading, most intense peak into neighboring peaks and consequently strongly postpones the collapse. The dependence of the critical input amplitude for the appearance of a fast collapse on the beam width is studied for wave packets with zero and nonzero topological charges. Wave packets carrying angular momentum are found to be much more resistant to the rapid collapse.}}, author = {{Driben, Rodislav and Meier, Torsten}}, issn = {{0146-9592}}, journal = {{Optics Letters}}, number = {{19}}, pages = {{5539--5542}}, title = {{{Nonlinear dynamics of Airy-vortex 3D wave packets: emission of vortex light waves}}}, doi = {{10.1364/ol.39.005539}}, volume = {{39}}, year = {{2014}}, } @article{22954, abstract = {{The dynamics of two component-coupled vectorial Airy beams is investigated. In the linear propagation regime, a complete analytic solution describes the breather-like propagation of two components that feature nondiffracting self-accelerating Airy behavior. The superposition of two beams with different input properties opens the possibility of designing more complex nondiffracting propagation scenarios. In the strongly nonlinear regime, the dynamics remain qualitatively robust as is revealed by direct numerical simulations. Because of the Kerr effect, the two beams emit solitonic breathers whose coupling period is compatible with the remaining Airy-like beams. The results of this study are relevant for the description of photonic and plasmonic beams that propagate in coupled planar waveguides, as well as for birefrigent or multiwavelength beams.}}, author = {{Driben, R. and Konotop, V. V. and Meier, Torsten}}, issn = {{0146-9592}}, journal = {{Optics Letters}}, number = {{19}}, pages = {{5523--5526}}, title = {{{Coupled Airy breathers}}}, doi = {{10.1364/ol.39.005523}}, volume = {{39}}, year = {{2014}}, } @inproceedings{3939, abstract = {{Optical and infrared antennas provide a promising way to couple photons in and out of nanoscale structures. As counterpart to conventional radio antennas, they are able to increase optical felds in sub-wavelength volumes, to enhance excitation and emission of quantum emitters or to direct light, radiated by quantum emitters. The directed emission of these antennas has been mainly pursued by surface plasmon based devices, e.g. Yagi-Uda like antennas, which are rather complicated due to the coupling of several metallic particles. Also, like all metallic structures in optical or infrared regime, these devices are very sensitive to fabrication tolerances and are affected by strong losses. It has been shown recently, that such directed emission can be accomplished by dielectric materials as well. In this paper we present an optimization of nanoscopic antennas in the near infrared regime starting from a metallic Yagi-Uda structure. The optimization is done via a particle-swarm algorithm, using full time domain finite integration simulations to obtain the characteristics of the investigated structure, also taking into account substrates. Furthermore we present a dielectric antenna, which performs even better, due to the lack of losses by an appropriate choice of the dielectric material. These antennas are robust concerning fabrication tolerances and can be realized with different materials for both the antenna and the substrate, without using high index materials.}}, author = {{Hildebrandt, Andre and Reichelt, Matthias and Meier, Torsten and Förstner, Jens}}, booktitle = {{Ultrafast Phenomena and Nanophotonics XVIII}}, editor = {{Betz, Markus and Elezzabi, Abdulhakem Y. and Song, Jin-Joo and Tsen, Kong-Thon}}, keywords = {{tet_topic_opticalantenna}}, pages = {{89841G--8941G--6}}, publisher = {{SPIE}}, title = {{{Engineering plasmonic and dielectric directional nanoantennas}}}, doi = {{10.1117/12.2036588}}, volume = {{8984}}, year = {{2014}}, } @article{15864, abstract = {{Starting from the extended Su-Schrieffer-Heeger model, multiband semiconductor Bloch equations are formulated in momentum space and applied to the analysis of the linear optical response of semiconducting carbon nanotubes (SCNTs). This formalism includes the coupling of electron-hole pair excitations between different valence and conduction bands, originating from the electron-hole Coulomb attraction. The influence of these couplings, which are referred to as nondiagonal interband Coulomb interaction (NDI-CI), on the linear excitonic absorption spectra is investigated and discussed for light fields polarized parallel to the tube direction. The results show that the intervalley NDI-CI leads to a significant increase of the band gap and a decrease of the exciton binding energy that results in a blueshift of the lowest-frequency excitonic absorption peak. The strength of these effects depends on the symmetry of the SCNT. Furthermore, for zigzag SCNTs with higher symmetry other nonintervalley NDI-CI terms also affect the spectral positions of excitonic absorption peaks.}}, author = {{Liu, Hong and Schumacher, Stefan and Meier, Torsten}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, number = {{15}}, title = {{{Influence of Coulomb-induced band couplings on linear excitonic absorption spectra of semiconducting carbon nanotubes}}}, doi = {{10.1103/physrevb.89.155407}}, volume = {{89}}, year = {{2014}}, } @article{22958, abstract = {{Dispersion management of periodically alternating fiber sections with opposite signs of two leading dispersion terms is applied for the regeneration of self-accelerating truncated Airy pulses. It is demonstrated that for such a dispersion management scheme, the direction of the acceleration of the pulse is reversed twice within each period. In this scheme the system features light hot spots in the center of each fiber section, where the energy of the light pulse is tightly focused in a short temporal slot. Comprehensive numerical studies demonstrate a long-lasting propagation also under the influence of a strong fiber Kerr nonlinearity.}}, author = {{Driben, R. and Meier, Torsten}}, issn = {{1050-2947}}, journal = {{Physical Review A}}, number = {{4}}, title = {{{Regeneration of Airy pulses in fiber-optic links with dispersion management of the two leading dispersion terms of opposite signs}}}, doi = {{10.1103/physreva.89.043817}}, volume = {{89}}, year = {{2014}}, }