@article{8614, author = {{Bryja, L. and Wójs, A. and Jadczak, J. and Misiewicz, J. and Płochocka, P. and Potemski, M. and Reuter, Dirk and Wieck, A.}}, issn = {{0587-4246}}, journal = {{Acta Physica Polonica A}}, pages = {{1073--1077}}, title = {{{Evidence of Singlet-Triplet Crossing in Photoluminescence of Positively Charged Excitons in GaAs Quantum Wells}}}, doi = {{10.12693/aphyspola.114.1073}}, year = {{2016}}, } @article{8748, author = {{Pulizzi, F. and Christianen, P.C.M. and Maan, J.C. and Eshlaghi, S. and Reuter, Dirk and Wieck, A.D.}}, issn = {{0587-4246}}, journal = {{Acta Physica Polonica A}}, pages = {{397--402}}, title = {{{From Localised to Ballistic Excitons in GaAs Quantum Wells}}}, doi = {{10.12693/aphyspola.100.397}}, year = {{2016}}, } @article{8769, author = {{Pulizzi, F. and Christianen, P.C.M. and Maan, J.C. and Eshlaghi, S. and Reuter, Dirk and Wieck, A.D.}}, issn = {{0587-4246}}, journal = {{Acta Physica Polonica A}}, pages = {{397--402}}, title = {{{From Localised to Ballistic Excitons in GaAs Quantum Wells}}}, doi = {{10.12693/aphyspola.100.397}}, year = {{2016}}, } @article{4244, abstract = {{In this work we study the resonant and coherent properties of single InP-based InAs quantum dots, which show an optical emission in the telecom C-band and L-band. High-resolution resonant photocurrent spectroscopy on p–i–n devices reveals narrow linewidths and fully resolved fine structure splittings. We observe Lorentzian line shapes, which allow for the extraction of dephasing times as a function of the applied bias voltage. Coherent ps laser excitation results in pronounced Rabi rotations with increasing pulse area. For π-pulse excitation, we obtain more than 93 % of the theoretically expected photocurrent amplitude. Our results also demonstrate that such state-of-the-art InP-based quantum dots for the telecom band exhibit promising key parameters comparable to well-established InAs/GaAs counterparts.}}, author = {{Gordon, S. and Yacob, M. and Reithmaier, J. P. and Benyoucef, M. and Zrenner, Artur}}, issn = {{0946-2171}}, journal = {{Applied Physics B}}, keywords = {{Bias Voltage, Optical Parametric Oscillator, Molecular Beam Epitaxy Growth, Internal Electric Field, Dephasing Time}}, number = {{2}}, publisher = {{Springer Nature}}, title = {{{Coherent photocurrent spectroscopy of single InP-based quantum dots in the telecom band at 1.5 µm}}}, doi = {{10.1007/s00340-015-6279-6}}, volume = {{122}}, year = {{2016}}, } @article{6533, abstract = {{We propose and implement a new concept for thermochromic plasmonic elements. It is based on vanadium dioxide (VO2) nanocrystals located in the near field of surface plasmon polaritons supported by an otherwise unstructured gold thin film. When the VO2 undergoes the metal-insulator phase transition, the coupling conditions for conversion of light into propagating surface plasmon polaritons change markedly. In particular, we realize thermochromic plasmonic grating couplers with substantial switching contrast as well as tunable plasmonic couplers in a Kretschmann configuration. The use of VO2 nanocrystals permits highly repetitive switching and room temperature operation. Simulations based on the actual dielectric function of our VO2 nanocrystals agree well with the experiment.}}, author = {{Jostmeier, Thorben and Mangold, Moritz and Zimmer, Johannes and Karl, Helmut and Krenner, Hubert J. and Ruppert, Claudia and Betz, Markus}}, issn = {{1094-4087}}, journal = {{Optics Express}}, number = {{15}}, publisher = {{The Optical Society}}, title = {{{Thermochromic modulation of surface plasmon polaritons in vanadium dioxide nanocomposites}}}, doi = {{10.1364/oe.24.017321}}, volume = {{24}}, year = {{2016}}, } @article{6539, abstract = {{Light is often characterized only by its classical properties, like intensity or coherence. When looking at its quantum properties, described by photon correlations, new information about the state of the matter generating the radiation can be revealed. In particular the difference between independent and entangled emitters, which is at the heart of quantum mechanics, can be made visible in the photon statistics of the emitted light. The well-studied phenomenon of superradiance occurs when quantum–mechanical correlations between the emitters are present. Notwithstanding, superradiance was previously demonstrated only in terms of classical light properties. Here, we provide the missing link between quantum correlations of the active material and photon correlations in the emitted radiation. We use the superradiance of quantum dots in a cavity-quantum electrodynamics laser to show a direct connection between superradiant pulse emission and distinctive changes in the photon correlation function. This directly demonstrates the importance of quantum–mechanical correlations and their transfer between carriers and photons in novel optoelectronic devices.}}, author = {{Jahnke, Frank and Gies, Christopher and Aßmann, Marc and Bayer, Manfred and Leymann, H. A. M. and Foerster, Alexander and Wiersig, Jan and Schneider, Christian and Kamp, Martin and Höfling, Sven}}, issn = {{2041-1723}}, journal = {{Nature Communications}}, number = {{1}}, publisher = {{Springer Nature America, Inc}}, title = {{{Giant photon bunching, superradiant pulse emission and excitation trapping in quantum-dot nanolasers}}}, doi = {{10.1038/ncomms11540}}, volume = {{7}}, year = {{2016}}, } @article{1460, author = {{Xiao, Shiyi and Mühlenbernd, Holger and Li, Guixin and Kenney, Mitchell and Liu, Fu and Zentgraf, Thomas and Zhang, Shuang and Li, Jensen}}, issn = {{2195-1071}}, journal = {{Advanced Optical Materials}}, number = {{5}}, pages = {{654--658}}, publisher = {{Wiley-Blackwell}}, title = {{{Helicity-Preserving Omnidirectional Plasmonic Mirror}}}, doi = {{10.1002/adom.201500705}}, volume = {{4}}, year = {{2016}}, } @article{1455, author = {{Zentgraf, Thomas}}, issn = {{0031-9252}}, journal = {{Physik in unserer Zeit}}, number = {{4}}, pages = {{163--164}}, publisher = {{Wiley-Blackwell}}, title = {{{Doppler-Effekt für rotierende Objekte}}}, doi = {{10.1002/piuz.201690063}}, volume = {{47}}, year = {{2016}}, } @inproceedings{24266, abstract = {{Recently electronic-photonic integrated circuits (EPIC) technology platforms became available [1] which allow fabrication of very compact and fast monolithic receivers. However, although the cointegration of electronics and photonics on the same chip allows for novel circuit topologies which could help to improve circuit performance quite often transmitter and receiver circuit design is using more or less conventional approaches. We propose a novel architecture that effectively utilizes the benefits of the EPIC technology such as: very short interconnects between the photodiode and the amplifier, symmetrical and compact photodiode structure with low operating voltages. Our architecture shown in Fig. 1 features fully-differential input stage, automatic biasing of the photodiode, DC coupling between diode and transimpedance amplifier (TIA) and very small footprint.}}, author = {{Gudyriev, Sergiy and Scheytt, Christoph and Meister, Stefan and Knoll, Dieter and Lischke, Stefan and Zimmermann, Lars and Meuer, Christian}}, booktitle = {{IEEE Group IV Photonics Conference}}, title = {{{ Low-Power, Ultra-compact, Fully-differential 40Gbps Direct Detection Receiver in 0.25μm Photonic BiCMOS SiGe Technology}}}, doi = {{10.1109/GROUP4.2016.7739126}}, year = {{2016}}, } @inproceedings{24267, author = {{Scheytt, Christoph}}, booktitle = {{Microelectronics Seminar}}, title = {{{Recent Advances in Millimeter-Wave-and Electronic-Photonic System-on-Chip Design}}}, year = {{2016}}, } @inproceedings{24268, author = {{Scheytt, Christoph}}, booktitle = {{DFG Rundgespräch:"Disruptive system concepts using electronic-photonic integration}}, title = {{{Electronic-Photonic System-On-Chip}}}, year = {{2016}}, } @article{4239, abstract = {{Confocal Raman spectroscopy is applied to identify ferroelectric domain structure sensitive phonon modes in potassium titanyl phosphate. Therefore, polarization-dependent measurements in various scattering configurations have been performed to characterize the fundamental Raman spectra of the material. The obtained spectra are discussed qualitatively based on an internal mode assignment. In the main part of this work, we have characterized z-cut periodically poled potassium titanyl phosphate in terms of polarity- and structure-sensitive phonon modes. Here, we find vibrations whose intensities are linked to the ferroelectric domain walls. We interpret this in terms of changes in the polarizability originating from strain induced by domain boundaries and the inner field distribution. Hence, a direct and 3D visualization of ferroelectric domain structures becomes possible in potassium titanyl phosphate.}}, author = {{Rüsing, Michael and Eigner, Christof and Mackwitz, P. and Berth, Gerhard and Silberhorn, Christine and Zrenner, Artur}}, issn = {{0021-8979}}, journal = {{Journal of Applied Physics}}, number = {{4}}, publisher = {{AIP Publishing}}, title = {{{Identification of ferroelectric domain structure sensitive phonon modes in potassium titanyl phosphate: A fundamental study}}}, doi = {{10.1063/1.4940964}}, volume = {{119}}, year = {{2016}}, } @article{3888, abstract = {{We successfully developed a process to fabricate freestanding cubic aluminium nitride (c-AlN) membranes containing cubic gallium nitride (c-GaN) quantum dots (QDs). The samples were grown by plasma assisted molecular beam epitaxy (MBE). To realize the photonic crystal (PhC) membrane we have chosen a triangular array of holes. The array was fabricated by electron beam lithography and several steps of reactive ion etching (RIE) with the help of a hard mask and an undercut of the active layer. The r/a- ratio of 0.35 was deter- mined by numerical simulations to obtain a preferably wide photonic band gap. Micro-photoluminescence (μ-PL) measurements of the photonic crystals, in particular of a H1 and a L3 cavity, and the emission of the QD ensemble were performed to characterize the samples. The PhCs show high quality factors of 4400 for the H1 cavity and about 5000/3000 for two different modes of the L3 cavity, respectively. The energy of the fundamental modes is in good agreement to the numerical simulations. }}, author = {{Blumenthal, Sarah and Bürger, Matthias and Hildebrandt, Andre and Förstner, Jens and Weber, Nils and Meier, Cedrik and Reuter, Dirk and As, Donat J.}}, issn = {{1862-6351}}, journal = {{physica status solidi (c)}}, keywords = {{tet_topic_phc, tet_topic_qd}}, number = {{5-6}}, pages = {{292--296}}, publisher = {{Wiley}}, title = {{{Fabrication and characterization of two-dimensional cubic AlN photonic crystal membranes containing zincblende GaN quantum dots}}}, doi = {{10.1002/pssc.201600010}}, volume = {{13}}, year = {{2016}}, } @article{4237, abstract = {{We report the fabrication of periodically poled domain patterns in x-cut lithium niobate thin-film. Here, thin films on insulator have drawn particular attention due to their intrinsic waveguiding properties offering high mode confinement and smaller devices compared to in-diffused waveguides in bulk material. In contrast to z-cut thin film lithium niobate, the x-cut geometry does not require back electrodes for poling. Further, the x-cut geometry grants direct access to the largest nonlinear and electro-optical tensor element, which overall promises smaller devices. The domain inversion was realized via electric field poling utilizing deposited aluminum top electrodes on a stack of LN thin film/SiO2 layer/Bulk LN, which were patterned by optical lithography. The periodic domain inversion was verified by non-invasive confocal second harmonic microscopy. Our results show domain patterns in accordance to the electrode mask layout. The second harmonic signatures can be interpreted in terms of spatially, overlapping domain filaments which start their growth on the þz side.}}, author = {{Mackwitz, P. and Rüsing, Michael and Berth, Gerhard and Widhalm, A. and Müller, K. and Zrenner, Artur}}, issn = {{0003-6951}}, journal = {{Applied Physics Letters}}, number = {{15}}, publisher = {{AIP Publishing}}, title = {{{Periodic domain inversion in x-cut single-crystal lithium niobate thin film}}}, doi = {{10.1063/1.4946010}}, volume = {{108}}, year = {{2016}}, } @article{4240, abstract = {{Cubic gallium nitride (GaN) films are analyzed with highresolution X-ray diffraction (HRXRD) and Raman spectroscopy. Several cubic GaN layers were grown on 3C-SiC (001) substrate by radio-frequency plasma-assisted molecular beam epitaxy. The layer thickness of the cubic GaN was varied between 75 and 505 nm. The HRXRD analysis reveals a reduction of the full-width at half-maximum (FWHM) of omega scans for growing layer thicknesses, which is caused by a partial compensation of defects. The Raman characterization confirms well-formed c-GaN layers. A more detailed examination of the longitudinal optical mode hints at a correlation of the FWHM of the Raman mode with the dislocation density, which shows the possibility to determine dislocation densities by Ramanspectroscopy on a micrometer scale, which is not possible by HRXRD. Furthermore, this Raman analysis shows that normalized Raman spectra present an alternative way to determine layer thicknesses of thin GaN films.}}, author = {{Rüsing, Michael and Wecker, T. and Berth, Gerhard and As, Donat Josef and Zrenner, Artur}}, issn = {{0370-1972}}, journal = {{physica status solidi (b)}}, keywords = {{cubic gallium nitride, dislocation density, HRXRD, Raman spectroscopy}}, number = {{4}}, pages = {{778--782}}, publisher = {{Wiley}}, title = {{{Joint Raman spectroscopy and HRXRD investigation of cubic gallium nitride layers grown on 3C-SiC}}}, doi = {{10.1002/pssb.201552592}}, volume = {{253}}, year = {{2016}}, } @article{10026, abstract = {{Congruent lithium niobate and lithium tantalate mixed crystals have been grown over the complete compositional range with the Czochralski method. The structural and vibrational properties of the mixed crystals are studied extensively by x-ray diffraction measurements, Raman spectroscopy, and density functional theory. The measured lattice parameters and vibrational frequencies are in good agreement with our theoretical predictions. The observed dependence of the Raman frequencies on the crystal composition is discussed on the basis of the calculated phonon displacement patterns. The phononic contribution to the static dielectric tensor is calculated by means of the generalized Lyddane-Sachs-Teller relation. Due to the pronounced dependence of the optical response on the Ta concentration, lithium niobate tantalate mixed crystals represent a perfect model system to study the properties of uniaxial mixed ferroelectric materials for application in integrated optics.}}, author = {{Rüsing, Michael and Sanna, Simone and Neufeld, Sergej and Berth, Gerhard and Schmidt, Wolf Gero and Zrenner, Artur and Yu, H. and Wang, Y. and Zhang, H.}}, issn = {{2469-9950}}, journal = {{Physical Review B}}, title = {{{Vibrational properties of LiNb1−xTaxO3 mixed crystals}}}, doi = {{10.1103/physrevb.93.184305}}, year = {{2016}}, } @article{39674, author = {{Atorf, B. and Rasouli, H. and Nordendorf, G. and Wilkes, D. and Kitzerow, Heinz-Siegfried}}, issn = {{0003-6951}}, journal = {{Applied Physics Letters}}, keywords = {{Physics and Astronomy (miscellaneous)}}, number = {{8}}, publisher = {{AIP Publishing}}, title = {{{Near infrared Kerr effect and description of field-induced phase transitions in polymer-stabilized blue phase liquid crystals}}}, doi = {{10.1063/1.4942604}}, volume = {{108}}, year = {{2016}}, } @article{39968, author = {{Dunmur, David and Kitzerow, Heinz-Siegfried}}, issn = {{1358-314X}}, journal = {{Liquid Crystals Today}}, keywords = {{Materials Chemistry, Inorganic Chemistry, Condensed Matter Physics}}, number = {{2}}, pages = {{24--29}}, publisher = {{Informa UK Limited}}, title = {{{The International Liquid Crystal Society 1990–2015}}}, doi = {{10.1080/1358314x.2016.1151994}}, volume = {{25}}, year = {{2016}}, } @article{39669, abstract = {{

Polymer-stabilized blue phase liquid crystal in-plane switching cell.

}}, author = {{Nordendorf, Gaby and Schmidtke, Jürgen and Wilkes, David and Kitzerow, Heinz-Siegfried}}, issn = {{2050-7526}}, journal = {{Journal of Materials Chemistry C}}, keywords = {{Materials Chemistry, General Chemistry}}, number = {{3}}, pages = {{518--521}}, publisher = {{Royal Society of Chemistry (RSC)}}, title = {{{Temperature-insensitive electro-optic response of polymer-stabilized blue phases}}}, doi = {{10.1039/c6tc04679g}}, volume = {{5}}, year = {{2016}}, } @article{39673, author = {{Wahle, M. and Ebel, J. and Wilkes, D. and Kitzerow, Heinz-Siegfried}}, issn = {{1094-4087}}, journal = {{Optics Express}}, keywords = {{Atomic and Molecular Physics, and Optics}}, number = {{20}}, publisher = {{The Optical Society}}, title = {{{Asymmetric band gap shift in electrically addressed blue phase photonic crystal fibers}}}, doi = {{10.1364/oe.24.022718}}, volume = {{24}}, year = {{2016}}, }