@article{43255, abstract = {{By means of direct simulations and theoretical analysis, we study the nonlinear propagation of truncated Airy pulses in an optical fiber exhibiting both anomalous second-order and strong positive third-order dispersions (TOD). It is found that the Airy pulse first reaches a finite-size focal area as determined by the relative strength of the two dispersion terms, and then undergoes an inversion transformation such that it continues to travel with an opposite acceleration. The system notably features tight focusing if the TOD is a dominant factor. These effects are partially reduced by Kerr nonlinearity.}}, author = {{Driben, R. and Hu, Y. and Chen, Z. and Malomed, B.A. and Morandotti, R.}}, journal = {{Optics Letters}}, number = {{14}}, pages = {{2499--2501}}, title = {{{Inversion and tight focusing of Airy pulses under the action of third-order dispersion}}}, doi = {{10.1364/OL.38.002499}}, volume = {{38}}, year = {{2013}}, } @article{43258, abstract = {{We consider an effectively one-dimensional binary Bose-Einstein condensate (BEC) with nonlinear repulsive interactions and linear spin-orbit (SO) and Zeeman-splitting couplings. In the presence of the trapping harmonic-oscillator (HO) potential, we report the existence of even, odd, and asymmetric spatial modes. They feature alternating domains with opposite directions of the pseudospin, i.e., antiferromagnetic structures, which is explained by the interplay of the linear couplings, HO confinement, and repulsive self-interaction. The number of the domains is determined by the strength of the SO coupling. The modes are constructed analytically in the weakly nonlinear system. The dynamical stability of the modes is investigated by means of the Bogoliubov–de Gennes equations and direct simulations. A notable result is that the multi-domain-wall (DW) structures are stable, alternating between odd and even shapes, while the simplest single-DW structure is unstable. Thus, the system features a transition to the complex ground states under the action of the SO coupling. The addition of the Zeeman splitting transforms the odd modes into asymmetric ones via spontaneous symmetry breaking. The results suggest possibilities for switching the binary system between states with opposite (pseudo)magnetization by external fields, and realization of similar stable states and dynamical effects in solid-state and nonlinear-optical settings emulated by the SO-coupled BECs.}}, author = {{Zezyulin, D.A. and Driben, R. and Konotop, V.V. and Malomed, B.A.}}, journal = {{Physical Review A }}, number = {{1}}, title = {{{Nonlinear modes in binary bosonic condensates with pseudo–spin-orbital coupling}}}, doi = {{10.1103/PhysRevA.88.013607}}, volume = {{88}}, year = {{2013}}, } @article{43257, abstract = {{We demonstrate that trapping of dispersive waves between two optical solitons takes place when resonant scattering of the waves on the solitons leads to nearly perfect reflections. The momentum transfer from the radiation to solitons results in their mutual attraction and a subsequent collision. The spectrum of the trapped radiation can either expand or shrink in the course of the propagation, which is controlled by arranging either collision or separation of the solitons.}}, author = {{Yulin, A. V. and Driben, R. and Malomed, B.A. and Skryabin, D.V.}}, journal = {{Optics Express}}, number = {{12}}, title = {{{Soliton interaction mediated by cascaded four wave mixing with dispersive waves}}}, doi = {{10.1364/OE.21.014481}}, volume = {{21}}, year = {{2013}}, } @inproceedings{4039, abstract = {{We perform experiments on resonant second-harmonic generation from planar gold split-ring-resonator arrays under normal incidence of light as a function of the lattice constant. Optimum nonlinear conversion occurs at intermediate lattice constants.}}, author = {{Niesler, Fabian B. and Linden, Stefan and Förstner, Jens and Grynko, Yevgen and Meier, Torsten and Wegener, Martin}}, booktitle = {{Conference on Lasers and Electro-Optics 2012}}, isbn = {{9781557529435}}, keywords = {{tet_topic_shg, tet_topic_meta}}, location = {{San Jose, California United States}}, number = {{1}}, publisher = {{OSA}}, title = {{{Collective effects in second-harmonic generation from split-ring-resonator arrays}}}, doi = {{10.1364/qels.2012.qth3e.2}}, volume = {{109}}, year = {{2013}}, } @inproceedings{3961, abstract = {{Previous experimental measurements and numerical simulations give evidence of strong electric and magnetic field interaction between split-ring resonators in dense arrays. One can expect that such interactions have an influence on the second harmonic generation. We apply the Discontinuous Galerkin Time Domain method and the hydrodynamic Maxwell-Vlasov model to simulate the linear and nonlinear optical response from SRR arrays. The simulations show that dense placement of the constituent building blocks appears not always optimal and collective effects can lead to a significant suppression of the near fields at the fundamental frequency and, consequently, to the decrease of the SHG intensity. We demonstrate also the great role of the symmetry degree of the array layout which results in the variation of the SHG efficiency in range of two orders of magnitude.}}, author = {{Grynko, Yevgen and Meier, Torsten and Linden, Stefan and Niesler, Fabian B. P. and Wegener, Martin and Förstner, Jens}}, booktitle = {{Ultrafast Phenomena and Nanophotonics XVII}}, editor = {{Betz, Markus and Elezzabi, Abdulhakem Y. and Song, Jin-Joo and Tsen, Kong-Thon}}, keywords = {{tet_topic_shg, tet_topic_meta}}, pages = {{86230L--86230L--9}}, publisher = {{SPIE}}, title = {{{Optimal second-harmonic generation in split-ring resonator arrays}}}, doi = {{10.1117/12.2003279}}, volume = {{8623}}, year = {{2013}}, } @article{15871, abstract = {{We derive a transparent and easy-to-use analytic expression for the selection rules and the optical dipole matrix elements for carbon nanotubes of arbitrary chirality in the presence of axial magnetic fields using a single-orbital π-electron tight-binding model. From this, we calculate the linear absorption spectrum for arbitrary polarization directions of the incident light, providing insight into all optically allowed transition. We show that the transverse absorption peaks can be selectively excited with circularly polarized light and spectrally resolved in an axial magnetic field.}}, author = {{Liu, Hong and Schumacher, Stefan and Meier, Torsten}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, number = {{3}}, title = {{{Selection rules and linear absorption spectra of carbon nanotubes in axial magnetic fields}}}, doi = {{10.1103/physrevb.88.035429}}, volume = {{88}}, year = {{2013}}, } @article{22952, author = {{Sternemann, E. and Jostmeier, T. and Ruppert, C. and Duc, H. T. and Meier, Torsten and Betz, M.}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, number = {{16}}, title = {{{Femtosecond quantum interference control of electrical currents in GaAs: Signatures beyond the perturbative χ(3) limit}}}, doi = {{10.1103/physrevb.88.165204}}, volume = {{88}}, year = {{2013}}, } @inproceedings{3980, abstract = {{Paper Abstract High harmonic generation is investigated for a two-band model of a semiconductor nanostructure. Similar to an atomic two-level system, the semiconductor emits high harmonic radiation. We show how one can specifically enhance the emission for a given frequency by applying a non-trivially shaped laser pulse. Therefore, the semiconductor Bloch equations including the interband and additionally the intraband dynamics are solved numerically and the spectral shape of the input pulse is computed via an optimization algorithm. It is demonstrated that desired emission frequencies can be favored even though the overall input power is kept constant. We also suggest special metallic nano geometries to achieve enhanced localized optical fields. They are found by geometric optimization.}}, author = {{Reichelt, Matthias and Hildebrandt, Andre and Walther, Andrea and Förstner, Jens and Meier, Torsten}}, booktitle = {{Ultrafast Phenomena and Nanophotonics XVI}}, isbn = {{9780819489036 }}, keywords = {{tet_topic_shg}}, publisher = {{SPIE}}, title = {{{Engineering high harmonic generation in semiconductors via pulse shaping}}}, doi = {{10.1117/12.906338}}, volume = {{8260}}, year = {{2012}}, } @article{22953, abstract = {{The generation of specific high harmonics for an optical two-level system is elucidated. The desired emitted radiation can be induced by a carefully designed excitation pulse, which is found by a multiparameter optimization procedure. The presented mechanism can also be applied to semiconductor structures for which the calculations result in much higher emission frequencies. The optimization procedure is either performed using a genetic algorithm or a rigorous mathematical optimization technique.}}, author = {{Reichelt, Matthias and Walther, Andrea and Meier, Torsten}}, issn = {{0740-3224}}, journal = {{Journal of the Optical Society of America B}}, number = {{2}}, title = {{{Tailoring the high-harmonic emission in two-level systems and semiconductors by pulse shaping}}}, doi = {{10.1364/josab.29.000a36}}, volume = {{29}}, year = {{2012}}, } @article{3972, abstract = {{Using a finite-difference time-domain method, we theoretically investigate the optical spectra of crossing perpendicular photonic crystal waveguides with quantum dots embedded in the central rod. The waveguides are designed so that the light mainly propagates along one direction and the cross talk is greatly reduced in the transverse direction. It is shown that when a quantum dot (QD) is resonant with the cavity, strong coupling can be observed via both the transmission and crosstalk spectrum. If the cavity is far off-resonant from the QD, both the cavity mode and the QD signal can be detected in the transverse direction since the laser field is greatly suppressed in this direction. This structure could have strong implications for resonant excitation and in-plane detection of QD optical spectroscopy.}}, author = {{Song, Xiaohong and Declair, Stefan and Meier, Torsten and Zrenner, Artur and Förstner, Jens}}, issn = {{1094-4087}}, journal = {{Optics Express}}, keywords = {{tet_topic_phc, tet_topic_qd}}, number = {{13}}, pages = {{14130--14136}}, publisher = {{The Optical Society}}, title = {{{Photonic crystal waveguides intersection for resonant quantum dot optical spectroscopy detection}}}, doi = {{10.1364/oe.20.014130}}, volume = {{20}}, year = {{2012}}, } @inproceedings{3967, abstract = {{We simulate the linear and nonlinear optical response from split-ring resonator (SRR) arrays to study collective effects between the constituent SRRs that determine spectral properties of the second harmonic generation (SHG). We apply the Discontinuous Galerkin Time Domain (DGTD) method and the hydrodynamic Maxwell-Vlasov model to calculate the SHG emission. Our model is able to qualitatively reproduce and explain the non-monotonic dependence of the spectral SHG transmission measured experimentally for SRR arrays with different lattice constants}}, author = {{Grynko, Yevgen and Meier, Torsten and Linden, Stefan and Niesler, Fabian B. P. and Wegener, Martin and Förstner, Jens}}, keywords = {{tet_topic_meta, tet_topic_shg}}, location = {{Bad Honnef}}, number = {{1}}, pages = {{128--130}}, publisher = {{AIP Conference Proceedings}}, title = {{{Near-field coupling and second-harmonic generation in split-ring resonator arrays}}}, doi = {{10.1063/1.4750118}}, volume = {{1475}}, year = {{2012}}, } @article{3970, abstract = {{Optical experiments on second-harmonic generation from split-ring-resonator square arrays show a nonmonotonic dependence of the conversion efficiency on the lattice constant. This finding is interpreted in terms of a competition between dilution effects and linewidth or near-field changes due to interactions among the individual elements in the array.}}, author = {{Linden, S. and Niesler, F. B. P. and Förstner, Jens and Grynko, Yevgen and Meier, Torsten and Wegener, M.}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, keywords = {{tet_topic_shg, tet_topic_meta}}, number = {{1}}, publisher = {{American Physical Society (APS)}}, title = {{{Collective Effects in Second-Harmonic Generation from Split-Ring-Resonator Arrays}}}, doi = {{10.1103/physrevlett.109.015502}}, volume = {{109}}, year = {{2012}}, } @article{43200, abstract = {{A novel adaptive approach to compute the eigenenergies and eigenfunctions of the two-particle (electron-hole) Schrödinger equation including Coulomb attraction is presented. As an example, we analyze the energetically lowest exciton state of a thin one-dimensional semiconductor quantum wire in the presence of disorder which arises from the non-smooth interface between the wire and surrounding material. The eigenvalues of the corresponding Schrödinger equation, i.e., the one-dimensional exciton Wannier equation with disorder, correspond to the energies of excitons in the quantum wire. The wavefunctions, in turn, provide information on the optical properties of the wire. We reformulate the problem of two interacting particles that both can move in one dimension as a stationary eigenvalue problem with two spacial dimensions in an appropriate weak form whose bilinear form is arranged to be symmetric, continuous, and coercive. The disorder of the wire is modelled by adding a potential in the Hamiltonian which is generated by normally distributed random numbers. The numerical solution of this problem is based on adaptive wavelets. Our scheme allows for a convergence proof of the resulting scheme together with complexity estimates. Numerical examples demonstrate the behavior of the smallest eigenvalue, the ground state energies of the exciton, together with the eigenstates depending on the strength and spatial correlation of disorder.}}, author = {{Meier, Torsten and Mollet, Christian and Kunoth, Angela}}, journal = {{Communications in Computational Physics}}, number = {{1}}, pages = {{21--47}}, publisher = {{Cambridge University Press}}, title = {{{Excitonic Eigenstates of Disordered Semiconductor Quantum Wires: Adaptive Wavelet Computation of Eigenvalues for the Electron-Hole Schrödinger Equation}}}, doi = {{10.4208/cicp.081011.260712a}}, volume = {{14}}, year = {{2012}}, } @inproceedings{4312, abstract = {{The intensity dependence of optically-induced injection currents in semiconductor quantum wells is investigated numerically. Oscillatory behavior of the electron charge current transients as function of intensity and time is predicted and explained.}}, author = {{Pochwala, Michal and Duc, Huynh Thanh and Förstner, Jens and Meier, Torsten}}, booktitle = {{CLEO:2011 - Laser Applications to Photonic Applications}}, isbn = {{9781557529107}}, issn = {{2160-8989 }}, keywords = {{tet_topic_qw}}, location = {{Baltimore, Maryland (USA)}}, publisher = {{Optical Society of America}}, title = {{{Intensity dependence of optically-induced injection currents in semiconductor quantum wells}}}, doi = {{10.1364/qels.2011.qmk4}}, year = {{2011}}, } @inproceedings{4043, abstract = {{We present numerical results of the mutual coupling between photonic crystal cavities and semiconductor quantum dots. Normal mode splitting between a single cavity mode and a single quantum dot is shown under weak excitation, while under strong excitation Q‐factor dependent side bands appear, according to the AC‐Stark effect. Coupled photonic crystals, aligned parallel but displaced under a 30°‐angle for efficient coupling, show line splittings of all eigenmodes, if a single eigenmode is resonantly coupled to a single quantum dot. The mutual coupling of N resonant quantum dots to a single cavity mode results in a N−−√ scaling of the splitting, known from quantum optics, but corrected by the field amplitude fraction for not collocated quantum dots.}}, author = {{Declair, S. and Song, X. and Meier, Torsten and Förstner, Jens}}, booktitle = {{THE FOURTH INTERNATIONAL WORKSHOP 2011}}, keywords = {{tet_topic_phc, tet_topic_qd}}, location = {{Bad Honnef}}, number = {{123}}, pages = {{123--125}}, publisher = {{AIP}}, title = {{{Simulation of Mutual Coupling of Photonic Crystal Cavity Modes and Semiconductor Quantum Dots}}}, doi = {{10.1063/1.3644232}}, volume = {{1398}}, year = {{2011}}, } @article{44059, abstract = {{A novel adaptive wavelet based method is presented that allows us to compute eigenvalues and eigenvectors of the electronic Schrödinger equation. Our method outperforms direct discretization methods with equidistant grid spacings, in particular, for problems that involve several length scales. As an application we present numerical evaluations of the energetically lowest exciton states for ordered and disordered semiconductor quantum wires.}}, author = {{Meier, Torsten and Mollet, Christian and Kunoth, Angela}}, journal = {{AIP Conference Proceedings}}, number = {{1}}, pages = {{156--158}}, publisher = {{American Institute of Physics}}, title = {{{Wavelet‐Based Adaptive Computations of the Excitonic Eigenstates of Disordered Semiconductor Quantum Wires}}}, doi = {{10.1063/1.3644243}}, volume = {{1398}}, year = {{2011}}, } @inproceedings{4048, abstract = {{We present an ab-initio method for calculating nonlinear and nonlocal optical effects in metallic slabs with sub-wavelength thickness. We find a strong localization of the second-harmonic current at the metal-vacuum interface.}}, author = {{Wand, Mathias and Schindlmayr, Arno and Meier, Torsten and Förstner, Jens}}, booktitle = {{CLEO:2011 - Laser Applications to Photonic Applications }}, isbn = {{978-1-4577-1223-4}}, issn = {{2160-8989}}, keywords = {{tet_topic_shg}}, location = {{Baltimore, Maryland, United States}}, publisher = {{Optical Society of America}}, title = {{{Theoretical approach to the ultrafast nonlinear optical response of metal slabs}}}, doi = {{10.1364/CLEO_AT.2011.JTuI59}}, year = {{2011}}, } @article{43259, abstract = {{The extreme nonlinear terahertz response of initially unexcited intrinsic semiconductor nanostructures is studied theoretically by solving extended semiconductor Bloch equations numerically. The coupled dynamics of intraband acceleration and multiphoton interband transitions leads to high-harmonic generation up to several tens of the exciting terahertz frequency. It is shown that the actual cut-off frequency is determined by the band structure and not by the excitation strength.}}, author = {{Golde, D. and Kira, M. and Meier, Torsten and Koch, S.W.}}, journal = {{physica status solidi (b)}}, number = {{4}}, pages = {{863--866}}, publisher = {{WILEY‐VCH Verlag}}, title = {{{Microscopic theory of the extremely nonlinear terahertz response of semiconductors}}}, doi = {{10.1002/pssb.201000840}}, volume = {{248}}, year = {{2011}}, } @inproceedings{44060, abstract = {{In recent years, single-walled carbon nanotubes (SWCNTs) have received widespread attention due to their perfect quasi-one-dimensional structure and unique physical properties, as well as their potential for applications. In the present work, we calculate the band structure of SWCNTs using an atomistic tight-binding model including spin-orbit interaction. We combine this approach with a many-particle calculation of the nonlinear optical response using multi-band semiconductor Bloch equations. We show that, for SWCNTs lacking inversion symmetry, the intrinsic spin-orbit interaction can give rise to single-color photoinduced charge and spin currents. In particular, we study the influence of excitonic effects on these photoinduced currents and draw the analogy to recent investigations on single-color injection of photocurrents in semiconductor quantum wells.}}, author = {{Meier, Torsten and Liu, Hong and Duc, Huynh Thanh and Schumache, Stefan}}, booktitle = {{75. Annual meeting of the DPG and combined DPG Spring meeting}}, issn = {{0420-0195}}, location = {{Dresden, Germany}}, number = {{1}}, title = {{{Photocurrents in semiconductor carbon nanotubes with spin-orbit interaction}}}, volume = {{46}}, year = {{2011}}, } @inproceedings{44062, abstract = {{Optical two-dimensional Fourier transform spectroscopy has been used to study the properties of semiconductor nanostructures in four-wave-mixing like experiments. Applying a phenomenological level model, we numerically and analytically analyze the main features of excitonic and biexcitonic contributions in a semiconductor quantum well by solving the optical Bloch equations. The method is extended to three-dimensional Fourier transform spectroscopy to investigate a recent experiment.}}, author = {{Meier, Torsten and Wiebeler, Christian and Reichelt, Matthias}}, booktitle = {{ 75. Annual meeting of the DPG and combined DPG Spring meeting }}, issn = {{0420-0195}}, location = {{Dresden, Germany}}, number = {{1}}, title = {{{Analysis of multidimensional Fourier transform spectroscopy for semiconductors with a phenomenological level model}}}, volume = {{46}}, year = {{2011}}, }