TY - JOUR AU - Tscheuschner, Ralf D. AU - Hoch, Sascha AU - Leschinsky, Eva AU - Meier, Cedrik AU - Theis, Sabine AU - Wieck, Andreas D. ID - 7694 IS - 11 JF - International Journal of Modern Physics B SN - 0217-9792 TI - Robustness of the Quantum Hall Effect, Sample Size Versus Sample Topology, and Quality Control Management of III–V Molecular Beam Epitaxy VL - 12 ER - TY - JOUR AU - Eshlaghi, Soheyla AU - Meier, Cedrik AU - Suter, Dieter AU - Reuter, D. AU - Wieck, A. D. ID - 7693 IS - 11 JF - Journal of Applied Physics SN - 0021-8979 TI - Depth profile of the implantation-enhanced intermixing of Ga+ focused ion beam in AlAs/GaAs quantum wells VL - 86 ER - TY - JOUR AU - Diaconescu, Dorina AU - Hoch, Sascha AU - Heidtkamp, Christian AU - Meier, Cedrik AU - Reuter, Dirk AU - Wieck, Andreas D ID - 7691 JF - Physica B: Condensed Matter SN - 0921-4526 TI - A new peak in the bend resistance of a four-terminal device written by FIB implantation VL - 284-288 ER - TY - CONF AU - Reuter, D. AU - Meier, Cedrik AU - Alvarez, M. A. AU - Koch, J. AU - Wieck, A. D. ID - 7692 T2 - IECON Proc. TI - Laterally resolved doping by focused ion beam implantation ER - TY - JOUR AU - Heidtkamp, C. AU - Meier, Cedrik AU - Reuter, D. AU - Versen, M. AU - Hoch, S. AU - Diaconescu, D. AU - Wieck, A.D. ID - 7690 JF - Physica B: Condensed Matter SN - 0921-4526 TI - Tunable backscattering in quantum Hall systems induced by neighbouring gates VL - 284-288 ER - TY - JOUR AU - Reuter, Dirk AU - Meier, Cedrik AU - Álvarez, M. A. Serrano AU - Wieck, A. D. ID - 8767 JF - Applied Physics Letters SN - 0003-6951 TI - Increased thermal budget for selectively doped heterostructures by employing AlAs/GaAs superlattices VL - 79 ER - TY - JOUR AU - Reuter, Dirk AU - Meier, Cedrik AU - Seekamp, A AU - Wieck, A.D ID - 8737 JF - Physica E: Low-dimensional Systems and Nanostructures SN - 1386-9477 TI - Fabrication of two-dimensional in-plane gate transistors by focused ion beam doping VL - 13 ER - TY - JOUR AU - Reuter, D AU - Meier, Cedrik AU - Riedesel, C AU - Wieck, A D ID - 7684 IS - 6 JF - Semiconductor Science and Technology SN - 0268-1242 TI - Local two-dimensional electron gas formation in p-doped GaAs/InyGa1 yAs/AlxGa1 xAs heterostructures by focused Si-implantation doping VL - 17 ER - TY - JOUR AU - Rahm, M. AU - Raabe, J. AU - Pulwey, R. AU - Biberger, J. AU - Wegscheider, W. AU - Weiss, D. AU - Meier, Cedrik ID - 7685 IS - 10 JF - Journal of Applied Physics SN - 0021-8979 TI - Planar Hall sensors for micro-Hall magnetometry VL - 91 ER - TY - JOUR AU - Riedesel, C AU - Meier, Cedrik AU - Schafmeister, P AU - Reuter, D AU - Wieck, A.D ID - 7682 JF - Physica E: Low-dimensional Systems and Nanostructures SN - 1386-9477 TI - Fabrication of high quality two-dimensional electron gases by overgrowth of focused ion beam implantation doped AlxGa1−xAs VL - 17 ER - TY - JOUR AU - Reuter, D. AU - Riedesel, C. AU - Schafmeister, P. AU - Meier, Cedrik AU - Wieck, A. D. ID - 7683 IS - 3 JF - Applied Physics Letters SN - 0003-6951 TI - Fabrication of high-quality two-dimensional electron gases by overgrowth of focused-ion-beam-doped AlxGa1−xAs VL - 82 ER - TY - JOUR AU - Meier, Cedrik AU - Reuter, Dirk AU - Riedesel, Christof AU - Wieck, Andreas D. ID - 7681 IS - 10 JF - Journal of Applied Physics SN - 0021-8979 TI - Fabrication of two-dimensional electron systems by focused ion beam doping of III/V semiconductor heterostructures VL - 93 ER - TY - JOUR AU - Haberer, E. D. AU - Sharma, R. AU - Meier, Cedrik AU - Stonas, A. R. AU - Nakamura, S. AU - DenBaars, S. P. AU - Hu, E. L. ID - 7678 IS - 22 JF - Applied Physics Letters SN - 0003-6951 TI - Free-standing, optically pumped, GaN∕InGaN microdisk lasers fabricated by photoelectrochemical etching VL - 85 ER - TY - JOUR AU - Knipping, Jörg AU - Wiggers, Hartmut AU - Rellinghaus, Bernd AU - Roth, Paul AU - Konjhodzic, Denan AU - Meier, Cedrik ID - 7679 IS - 8 JF - Journal of Nanoscience and Nanotechnology SN - 1533-4880 TI - Synthesis of High Purity Silicon Nanoparticles in a Low Pressure Microwave Reactor VL - 4 ER - TY - JOUR AU - Wibbelhoff, O AU - Meier, Cedrik AU - Lorke, A AU - Schafmeister, P AU - Wieck, A.D ID - 7680 IS - 2-4 JF - Physica E: Low-dimensional Systems and Nanostructures SN - 1386-9477 TI - Wave function mapping of self-assembled quantum dots by capacitance spectroscopy VL - 21 ER - TY - JOUR AU - Reuter, D. AU - Kailuweit, P. AU - Wieck, A. D. AU - Zeitler, U. AU - Wibbelhoff, O. AU - Meier, Cedrik AU - Lorke, A. AU - Maan, J. C. ID - 7658 IS - 2 JF - Physical Review Letters SN - 0031-9007 TI - Coulomb-Interaction-Induced Incomplete Shell Filling in the Hole System of InAs Quantum Dots VL - 94 ER - TY - JOUR AU - Reuter, Dirk AU - Kailuweit, P. AU - Wieck, A. D. AU - Zeitler, U. AU - Wibbelhoff, O. AU - Meier, Cedrik AU - Lorke, A. AU - Maan, J. C. ID - 8674 JF - Physical Review Letters SN - 0031-9007 TI - Coulomb-Interaction-Induced Incomplete Shell Filling in the Hole System of InAs Quantum Dots ER - TY - CONF AU - Lüttjohann, S. AU - Meier, Cedrik AU - Lork, A. AU - Reuter, D. AU - Wieck, A. D. ID - 7677 T2 - Physics of Semiconductors TI - Emission from neutral and charged excitons in self-organized InAs quantum dots: Band bending vs. Pauli-blocking VL - 772 ER - TY - JOUR AU - Choi, Y.-S. AU - Hennessy, K. AU - Sharma, R. AU - Haberer, E. AU - Gao, Y. AU - DenBaars, S. P. AU - Nakamura, S. AU - Hu, E. L. AU - Meier, Cedrik ID - 7653 IS - 24 JF - Applied Physics Letters SN - 0003-6951 TI - GaN blue photonic crystal membrane nanocavities VL - 87 ER - TY - JOUR AU - Kravets, Vasyl G. AU - Meier, Cedrik AU - Konjhodzic, Denan AU - Lorke, Axel AU - Wiggers, Hartmut ID - 7657 IS - 8 JF - Journal of Applied Physics SN - 0021-8979 TI - Infrared properties of silicon nanoparticles VL - 97 ER - TY - JOUR AU - Haberer, E. D. AU - Meier, Cedrik AU - Sharma, R. AU - Stonas, A. R. AU - DenBaars, S. P. AU - Nakamura, S. AU - Hu, E. L. ID - 7676 IS - 7 JF - physica status solidi (c) SN - 1610-1634 TI - Observation of high Q resonant modes in optically pumped GaN/InGaN microdisks fabricated using photoelectrochemical etching VL - 2 ER - TY - CONF AU - Choi, Y.-S. AU - Meier, Cedrik AU - Sharma, R. AU - Hennessy, K. AU - Haberer, E. D. AU - Gao, Y. AU - Nakamura, S. AU - Hu, E. L. ID - 7671 SN - 0-7803-9242-6 T2 - 2005 Pacific Rim Conference on Lasers and Electro-Optics TI - Optical properties of GaN photonic crystal membrane nanocavities ER - TY - JOUR AU - David, A. AU - Meier, Cedrik AU - Sharma, R. AU - Diana, F. S. AU - DenBaars, S. P. AU - Hu, E. AU - Nakamura, S. AU - Weisbuch, C. AU - Benisty, H. ID - 7655 IS - 10 JF - Applied Physics Letters SN - 0003-6951 TI - Photonic bands in two-dimensionally patterned multimode GaN waveguides for light extraction VL - 87 ER - TY - JOUR AU - Chakraborty, Arpan AU - Keller, Stacia AU - Meier, Cedrik AU - Haskell, Benjamin A. AU - Keller, Salka AU - Waltereit, Patrick AU - DenBaars, Steven P. AU - Nakamura, Shuji AU - Speck, James S. AU - Mishra, Umesh K. ID - 7659 IS - 3 JF - Applied Physics Letters SN - 0003-6951 TI - Properties of nonpolar a-plane InGaN∕GaN multiple quantum wells grown on lateral epitaxially overgrown a-plane GaN VL - 86 ER - TY - JOUR AU - Lüttjohann, Stephan AU - Meier, Cedrik AU - Lorke, Axel AU - Reuter, Dirk AU - Wieck, Andreas D. ID - 7654 IS - 16 JF - Applied Physics Letters SN - 0003-6951 TI - Screening effects in InAs quantum-dot structures observed by photoluminescence and capacitance-voltage spectra VL - 87 ER - TY - JOUR AU - Schwenzer, Birgit AU - Meier, Cedrik AU - Masala, Ombretta AU - Seshadri, Ram AU - DenBaars, Steven P. AU - Mishra, Umesh K. ID - 7674 IS - 19 JF - Journal of Materials Chemistry SN - 0959-9428 TI - Synthesis of luminescing (In,Ga)N nanoparticles from an inorganic ammonium fluoride precursor VL - 15 ER - TY - JOUR AU - Sharma, R. AU - Haberer, E. D. AU - Meier, Cedrik AU - Hu, E. L. AU - Nakamura, S. ID - 7656 IS - 5 JF - Applied Physics Letters SN - 0003-6951 TI - Vertically oriented GaN-based air-gap distributed Bragg reflector structure fabricated using band-gap-selective photoelectrochemical etching VL - 87 ER - TY - JOUR AU - Regolin, I. AU - Sudfeld, D. AU - Lüttjohann, S. AU - Khorenko, V. AU - Prost, W. AU - Kästner, J. AU - Dumpich, G. AU - Meier, Cedrik AU - Lorke, A. AU - Tegude, F.-J. ID - 7646 JF - Journal of Crystal Growth SN - 0022-0248 TI - Growth and characterisation of GaAs/InGaAs/GaAs nanowhiskers on (111) GaAs VL - 298 ER - TY - JOUR AU - Russ, M. AU - Meier, Cedrik AU - Marquardt, B. AU - Lorke, A. AU - Reuter, D. AU - Wieck, A. D. ID - 7647 IS - 9-10 JF - Phase Transitions SN - 0141-1594 TI - Quantum dot electrons as controllable scattering centers in the vicinity of a two-dimensional electron gas VL - 79 ER - TY - JOUR AU - Nienhaus, H. AU - Kravets, V. AU - Koutouzov, S. AU - Meier, Cedrik AU - Lorke, A. AU - Wiggers, H. AU - Kennedy, M. K. AU - Kruis, F. E. ID - 7649 IS - 3 JF - Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures SN - 1071-1023 TI - Quantum size effect of valence band plasmon energies in Si and SnO[sub x] nanoparticles VL - 24 ER - TY - JOUR AU - Meier, Cedrik AU - Lüttjohann, Stephan AU - Kravets, Vasyl G. AU - Nienhaus, Hermann AU - Lorke, Axel AU - Wiggers, Hartmut ID - 7650 IS - 1-2 JF - Physica E: Low-dimensional Systems and Nanostructures SN - 1386-9477 TI - Raman properties of silicon nanoparticles VL - 32 ER - TY - JOUR AU - Meier, Cedrik AU - Lüttjohann, Stephan AU - Kravets, Vasyl G. AU - Nienhaus, Hermann AU - Lorke, Axel AU - Ifeacho, Pascal AU - Wiggers, Hartmut AU - Schulz, Christof AU - Kennedy, Marcus K. AU - Kruis, F. Einar ID - 7648 IS - 11 JF - Journal of Applied Physics SN - 0021-8979 TI - Vibrational and defect states in SnOx nanoparticles VL - 99 ER - TY - JOUR AU - Meier, Cedrik AU - Hennessy, Kevin AU - Haberer, Elaine D. AU - Sharma, Rajat AU - Choi, Yong-Seok AU - McGroddy, Kelly AU - Keller, Stacia AU - DenBaars, Steven P. AU - Nakamura, Shuji AU - Hu, Evelyn L. ID - 7651 IS - 3 JF - Applied Physics Letters SN - 0003-6951 TI - Visible resonant modes in GaN-based photonic crystal membrane cavities VL - 88 ER - TY - JOUR AU - Marquardt, Bastian AU - Russ, Marco AU - Lorke, Axel AU - Meier, Cedrik AU - Reuter, Dirk AU - Wieck, Andreas D. ID - 7641 IS - 6 JF - Physica E: Low-dimensional Systems and Nanostructures SN - 1386-9477 TI - Quantum dots as tunable scatterers for 2D- and 1D-electron systems VL - 40 ER - TY - JOUR AU - Meier, Cedrik AU - Gondorf, Andreas AU - Lüttjohann, Stephan AU - Lorke, Axel AU - Wiggers, Hartmut ID - 7643 IS - 10 JF - Journal of Applied Physics SN - 0021-8979 TI - Silicon nanoparticles: Absorption, emission, and the nature of the electronic bandgap VL - 101 ER - TY - JOUR AU - Meier, Cedrik AU - Hennessy, Kevin ID - 7644 IS - 14 JF - Applied Physics Letters SN - 0003-6951 TI - Technique for tilting GaAs photonic crystal nanocavities out of plane VL - 90 ER - TY - JOUR AU - Lüttjohann, S AU - Meier, Cedrik AU - Offer, M AU - Lorke, A AU - Wiggers, H ID - 7645 IS - 3 JF - Europhysics Letters (EPL) SN - 0295-5075 TI - Temperature-induced crossover between bright and dark exciton emission in silicon nanoparticles VL - 79 ER - TY - JOUR AU - Lei, W. AU - Offer, M. AU - Lorke, A. AU - Notthoff, C. AU - Meier, Cedrik AU - Wibbelhoff, O. AU - Wieck, A. D. ID - 7640 IS - 19 JF - Applied Physics Letters SN - 0003-6951 TI - Probing the band structure of InAs∕GaAs quantum dots by capacitance-voltage and photoluminescence spectroscopy VL - 92 ER - TY - CHAP AU - Meier, Cedrik AU - Lüttjohann, Stephan AU - Offer, Matthias AU - Wiggers, Hartmut AU - Lorke, Axel ID - 7500 SN - 1438-4329 T2 - Advances in Solid State Physics TI - Silicon Nanoparticles: Excitonic Fine Structure and Oscillator Strength ER - TY - CONF AU - Piegdon, Karoline A. AU - Matthias, Heinrich AU - Meier, Cedrik AU - Kitzerow, Heinz-Siegfried ED - Chien, Liang-Chy ID - 7642 T2 - Emerging Liquid Crystal Technologies III TI - Tunable optical properties of photonic crystals and semiconductor microdisks using liquid crystals ER - TY - CONF AB - We numerically investigate Whispering Gallery Modes (WGM) in a subwavelength microdisk resonator [1] embedded in an uniaxial anisotropic liquid crystal environment. It is shown that the WGMs have anticrossing behavior when modes of different radial mode order M or azimuthal order N approach each other spectrally. AU - Förstner, Jens AU - Declair, S. AU - Meier, Cedrik AU - Meier, Torsten ID - 4179 IS - 1 KW - tet_topic_microdisk T2 - Theoretical and Computational Nanophotonics Tacona-Photonics TI - Anticrossing of Whispering Gallery Modes in Microdisk Resonators Embedded in a Liquid Crystal VL - 1176 ER - TY - CONF AB - We experimentally and theoretically investigate microdisk resonators with embedded quantum dots immersed in a liquid crystal in its nematic phase, showing the tunabililty of the photonic modes via external parameters like temperature or electric field. AU - Förstner, Jens AU - Meier, Cedrik AU - Piegdon, Karoline AU - Declair, Stefan AU - Hoischen, Andreas AU - Urbanski, Mark AU - Meier, Torsten AU - Kitzerow, Heinz-Siegfried ID - 4181 KW - tet_topic_microdisk SN - 9781557528735 T2 - Advances in Optical Sciences Congress TI - Coupling Dynamics of Quantum Dots in a Liquid-Crystal-Tunable Microdisk Resonator ER - TY - JOUR AU - Lei, Wen AU - Notthoff, Christian AU - Offer, Matthias AU - Meier, Cedrik AU - Lorke, Axel AU - Jagadish, Chennupati AU - Wieck, Andreas D. ID - 7498 IS - 07 JF - Journal of Materials Research SN - 0884-2914 TI - Electron energy structure of self-assembled In(Ga)As nanostructures probed by capacitance-voltage spectroscopy and one-dimensional numerical simulation VL - 24 ER - TY - JOUR AU - Mehta, M. AU - Ruth, M. AU - Piegdon, K. A. AU - Krix, D. AU - Nienhaus, H. AU - Meier, Cedrik ID - 7497 IS - 5 JF - Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures SN - 1071-1023 TI - Inductively coupled plasma reactive ion etching of bulk ZnO single crystal and molecular beam epitaxy grown ZnO films VL - 27 ER - TY - JOUR AU - Huba, K. AU - Krix, D. AU - Meier, Cedrik AU - Nienhaus, H. ID - 7499 IS - 4 JF - Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films SN - 0734-2101 TI - Ultrathin K∕p-Si(001) Schottky diodes as detectors of chemically generated hot charge carriers VL - 27 ER - TY - JOUR AB - We have integrated individual (In,Ga)As quantum dots (QDs) using site-controlled molecular beam epitaxial growth into the intrinsic region of a p-i-n junction diode. This is achieved using an in situ combination of focused ion beam prepatterning, annealing, and overgrowth, resulting in arrays of individually electrically addressable (In,Ga)As QDs with full control on the lateral position. Using microelectroluminescence spectroscopy we demonstrate that these QDs have the same optical quality as optically pumped Stranski–Krastanov QDs with random nucleation located in proximity to a doped interface. The results suggest that this technique is scalable and highly interesting for different applications in quantum devices. AU - Mehta, M. AU - Reuter, Dirk AU - Wieck, A. D. AU - Michaelis de Vasconcellos, S. AU - Zrenner, Artur AU - Meier, Cedrik ID - 4550 IS - 14 JF - Applied Physics Letters SN - 0003-6951 TI - An intentionally positioned (In,Ga)As quantum dot in a micron sized light emitting diode VL - 97 ER - TY - JOUR AB - We numerically investigate the behavior of Whispering Gallery Modes (WGMs) in circularly shaped resonators like microdisks, with diameters in the range of optical vacuum wavelengths. The microdisk is embedded in an uniaxial anisotropic dielectric environment. By changing the optical anisotropy, one obtains spectral tunability of the optical modes. The degree of tunability strongly depends on the radial (azimuthal) mode order M (N). As the modes approach each other spectrally, anticrossing is observed, leading to a rearrangement of the optical states. AU - Declair, S. AU - Meier, Cedrik AU - Meier, Torsten AU - Förstner, Jens ID - 4125 IS - 4 JF - Photonics and Nanostructures - Fundamentals and Applications KW - tet_topic_microdisk SN - 1569-4410 TI - Anticrossing of Whispering Gallery Modes in microdisk resonators embedded in an anisotropic environment VL - 8 ER - TY - JOUR AU - Mehta, M. AU - Meier, Cedrik ID - 7494 IS - 2 JF - Journal of The Electrochemical Society SN - 0013-4651 TI - Controlled Etching Behavior of O-Polar and Zn-Polar ZnO Single Crystals VL - 158 ER - TY - JOUR AU - Theis, Jens AU - Geller, Martin AU - Lorke, Axel AU - Wiggers, Hartmut AU - Wieck, Andreas AU - Meier, Cedrik ID - 7496 IS - 45 JF - Nanotechnology SN - 0957-4484 TI - Electroluminescence from silicon nanoparticles fabricated from the gas phase VL - 21 ER - TY - JOUR AB - An intentional positioning of optically active quantum dots using site-selective growth by a combination of molecular beam epitaxy (MBE) and focused ion beam (FIB) implantation in an all-ultra-high-vacuum (UHV) setup has been successfully demonstrated. A square array of periodic holes on GaAs substrate was fabricated with FIB of 30 keV ions followed by an in situ annealing step. Subsequently, the patterned holes were overgrown with an optimized amount of InAs in order to achieve site-selective growth of the QDs on the patterned holes. Under well-optimized conditions, a selectivity of single quantum dot growth in the patterned holes of 52% was achieved. Thereafter, carrier injection and subsequent radiative recombination from the positioned InAs/GaAs self-assembled QDs was investigated by embedding the QDs in the intrinsic part of a GaAs-based p–i–n junction device. Electroluminescence spectra taken at 77 K show interband transitions up to the fifth excited state from the QDs. AU - Mehta, Minisha AU - Reuter, Dirk AU - Melnikov, Alexander AU - Wieck, Andreas D. AU - Michaelis de Vasconcellos, Steffen AU - Baumgarten, Tim AU - Zrenner, Artur AU - Meier, Cedrik ID - 4551 IS - 10 JF - Physica E: Low-dimensional Systems and Nanostructures KW - Molecular beam epitaxy KW - Focused ion beam KW - Self-assembled quantum dot KW - Electroluminescence SN - 1386-9477 TI - Intentionally positioned self-assembled InAs quantum dots in an electroluminescent p–i–n junction diode VL - 42 ER - TY - JOUR AB - GaAs-based semiconductor microdisks with high quality whispering gallery modes (Q44000) have been fabricated.A layer of self-organized InAs quantumdots (QDs) served as a light source to feed the optical modes at room temperature. In order to achieve frequency tuning of the optical modes, the microdisk devices have been immersed in 4 – cyano – 4´-pentylbiphenyl (5CB), a liquid crystal(LC) with a nematic phase below the clearing temperature of TC≈34°C .We have studied the device performance in the temperature rangeof T=20-50°C, in order to investigate the influence of the nematic–isotropic phase transition on the optical modes. Moreover,we havea pplied an AC electric field to the device,which leads in the nematic phase to a reorientation of the anisotropic dielectric tensor of the liquid crystal.This electrical anisotropy can be used to achieve electrical tunability of the optical modes.Using the finite-difference time domain (FDTD) technique with an anisotropic material model, we are able to describe the influence of the liquid crystal qualitatively. AU - Piegdon, Karoline A. AU - Offer, Matthias AU - Lorke, Axel AU - Urbanski, Martin AU - Hoischen, Andreas AU - Kitzerow, Heinz-Siegfried AU - Declair, Stefan AU - Förstner, Jens AU - Meier, Torsten AU - Reuter, Dirk AU - Wieck, Andreas D. AU - Meier, Cedrik ID - 4123 IS - 10 JF - Physica E: Low-dimensional Systems and Nanostructures KW - tet_topic_qd KW - tet_topic_microdisk SN - 1386-9477 TI - Self-assembled quantum dots in a liquid-crystal-tunable microdisk resonator VL - 42 ER - TY - JOUR AB - Microdisks made from GaAs with embedded InAs quantum dots are immersed in the liquid crystal 4-cyano-4’-pentylbiphenyl (5CB). The quantum dots serve as emitters feeding the optical modes of the photonic cavity. By changing temperature, the liquid crystal undergoes a phase transition from the isotropic to the nematic state, which can be used as an effective tuning mechanism of the photonic modes of the cavity. In the nematic state, the uniaxial electrical anisotropy of the liquid crystal molecules can be exploited for orienting the material in an electric field, thus externally controlling the birefringence of the material. Using this effect, an electric field induced tuning of the modes is achieved. Numerical simulations using the finite-differences time-domain (FDTD) technique employing an anisotropic dielectric medium allow to understand the alignment of the liquid crystal molecules on the surface of the microdisk resonator. AU - Piegdon, Karoline A. AU - Declair, Stefan AU - Förstner, Jens AU - Meier, Torsten AU - Matthias, Heiner AU - Urbanski, Martin AU - Kitzerow, Heinz-Siegfried AU - Reuter, Dirk AU - Wieck, Andreas D. AU - Lorke, Axel AU - Meier, Cedrik ID - 4172 IS - 8 JF - Optics Express KW - tet_topic_qd KW - tet_topic_microdisk SN - 1094-4087 TI - Tuning quantum-dot based photonic devices with liquid crystals VL - 18 ER - TY - JOUR AB - Using a combined all-ultra-high-vacuum process employing lateral patterning with focused ion beams and molecular beam epitaxy, site-selective growth of single (In,Ga)As quantum dots is achieved. We have embedded such a layer of intentionally positioned quantum dots in the intrinsic region of a p-i-n junction so that the quantum dots can be driven electrically. In this contribution, we will present our results on the morphological properties of the ion-beam modified surface on which the quantum dot nucleation occurs together with a characterization of the electrical and optoelectronic properties. We will demonstrate that a single, individual quantum dot can directly be electrically addressed. AU - Mehta, Minisha AU - Reuter, Dirk AU - Wieck, Andreas D. AU - Michaelis de Vasconcellos, Steffen AU - Zrenner, Artur AU - Meier, Cedrik ID - 4378 IS - 4 JF - physica status solidi (c) KW - molecular beam epitaxy KW - quantum dot KW - site control KW - electroluminescence SN - 1862-6351 TI - Electrically driven intentionally positioned single quantum dot VL - 8 ER - TY - JOUR AU - Urbanski, Martin AU - Piegdon, Karoline A. AU - Meier, Cedrik AU - Kitzerow, Heinz-Siegfried ID - 7495 IS - 4 JF - Liquid Crystals SN - 0267-8292 TI - Investigations on the director field around microdisc resonators VL - 38 ER - TY - JOUR AU - Piegdon, K. A. AU - Lexow, M. AU - Grundmeier, G. AU - Kitzerow, Heinz-Siegfried AU - Pärschke, K. AU - Mergel, D. AU - Reuter, Dirk AU - Wieck, A. D. AU - Meier, Cedrik ID - 7493 IS - 6 JF - Optics Express SN - 1094-4087 TI - All-optical tunability of microdisk lasers via photo-adressable polyelectrolyte functionalization VL - 20 ER - TY - JOUR AU - Kröger, Philipp AU - Ruth, Marcel AU - Weber, Nils AU - Meier, Cedrik ID - 7491 IS - 26 JF - Applied Physics Letters SN - 0003-6951 TI - Carrier localization in ZnO quantum wires VL - 100 ER - TY - JOUR AU - Kampmeier, J. AU - Rashad, M. AU - Woggon, U. AU - Ruth, M. AU - Meier, Cedrik AU - Schikora, D. AU - Lischka, K. AU - Pawlis, A. ID - 7492 IS - 15 JF - Physical Review B SN - 1098-0121 TI - Enhanced photoluminescence of colloidal nanocrystals embedded in epitaxially grown semiconductor microstructures VL - 85 ER - TY - JOUR AB - We report an anisotropic formation of defects in cubic GaN grown on nano-patterned 3C-SiC/Si (001) by molecular beam epitaxy. Nano-patterning of 3C-SiC/Si (001) is achieved by nanosphere lithography and a reactive ion etching process. Atomic force microscopy and scanning electron microscopy show that the selectivearea- grown cubic GaN nucleates in two structurally different domains, which most probably originate from the substrate. In adjacent domains the formation of defects, especially hexagonal inclusions, is different and leads to two different surface morphologies. The dominant phase within these domains was measured by electron backscatter diffraction. Optical properties were investigated by micro-photoluminescence and cathodoluminescence spectroscopy. AU - Kemper, R. M. AU - Häberlen, M. AU - Schupp, T. AU - Weinl, M. AU - Bürger, M. AU - Ruth, M. AU - Meier, Cedrik AU - Niendorf, T. AU - Maier, H. J. AU - Lischka, K. AU - As, D. J. AU - Lindner, Jörg ID - 4131 IS - 3-4 JF - physica status solidi (c) SN - 1862-6351 TI - Formation of defects in cubic GaN grown on nano-patterned 3C-SiC (001) VL - 9 ER - TY - JOUR AU - Ruth, Marcel AU - Meier, Cedrik ID - 7490 IS - 22 JF - Physical Review B SN - 1098-0121 TI - Scaling coefficient for three-dimensional grain coalescence of ZnO on Si(111) VL - 86 ER - TY - JOUR AU - Ruth, Marcel AU - Zentgraf, Thomas AU - Meier, Cedrik ID - 1705 IS - 21 JF - Optics Express SN - 1094-4087 TI - Blue-green emitting microdisks using low-temperature-grown ZnO on patterned silicon substrates VL - 21 ER - TY - JOUR AB - Microresonators containing quantum dots find application in devices like single photon emitters for quantum information technology as well as low threshold laser devices. We demonstrate the fabrication of 60 nm thin zinc-blende AlN microdisks including cubic GaN quantum dots using dry chemical etching techniques. Scanning electron microscopy analysis reveals the morphology with smooth surfaces of the microdisks. Micro-photoluminescence measurements exhibit optically active quantum dots. Furthermore this is the first report of resonator modes in the emission spectrum of a cubic AlN microdisk. AU - Bürger, M. AU - Kemper, R.M. AU - Bader, C.A. AU - Ruth, M. AU - Declair, S. AU - Meier, Cedrik AU - Förstner, Jens AU - As, D.J. ID - 3959 JF - Journal of Crystal Growth KW - tet_topic_qd KW - tet_topic_microdisk SN - 0022-0248 TI - Cubic GaN quantum dots embedded in zinc-blende AlN microdisks VL - 378 ER - TY - JOUR AU - Ruth, Marcel AU - Meier, Cedrik ID - 7488 IS - 7 JF - AIP Advances SN - 2158-3226 TI - Structural enhancement of ZnO on SiO2 for photonic applications VL - 3 ER - TY - JOUR AB - Whispering gallery modes (WGMs) were observed in 60 nm thin cubic AlN microdisk resonators containing a single layer of non-polar cubic GaN quantum dots. Freestanding microdisks were patterned by means of electron beam lithography and a two step reactive ion etching process. Micro-photoluminescence spectroscopy investigations were performed for optical characterization. We analyzed the mode spacing for disk diameters ranging from 2-4 lm. Numerical investigations using three dimensional finite difference time domain calculations were in good agreement with the experimental data. Whispering gallery modes of the radial orders 1 and 2 were identified by means of simulated mode field distributions. AU - Bürger, M. AU - Ruth, M. AU - Declair, S. AU - Förstner, Jens AU - Meier, Cedrik AU - As, Donat Josef ID - 3963 IS - 8 JF - Applied Physics Letters KW - tet_topic_qd KW - tet_topic_microdisk SN - 0003-6951 TI - Whispering gallery modes in zinc-blende AlN microdisks containing non-polar GaN quantum dots VL - 102 ER - TY - JOUR AU - Wiebeler, Christian AU - Bader, Christina A. AU - Meier, Cedrik AU - Schumacher, Stefan ID - 7485 IS - 28 JF - Phys. Chem. Chem. Phys. SN - 1463-9076 TI - Optical spectrum, perceived color, refractive index, and non-adiabatic dynamics of the photochromic diarylethene CMTE VL - 16 ER - TY - JOUR AU - Bader, Christina A. AU - Zeuner, Franziska AU - Bader, Manuel H. W. AU - Zentgraf, Thomas AU - Meier, Cedrik ID - 1696 IS - 21 JF - Journal of Applied Physics SN - 0021-8979 TI - Nonlinear optical sub-bandgap excitation of ZnO-based photonic resonators VL - 118 ER - TY - JOUR AB - 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. AU - Blumenthal, Sarah AU - Bürger, Matthias AU - Hildebrandt, Andre AU - Förstner, Jens AU - Weber, Nils AU - Meier, Cedrik AU - Reuter, Dirk AU - As, Donat J. ID - 3888 IS - 5-6 JF - physica status solidi (c) KW - tet_topic_phc KW - tet_topic_qd SN - 1862-6351 TI - Fabrication and characterization of two-dimensional cubic AlN photonic crystal membranes containing zincblende GaN quantum dots VL - 13 ER - TY - JOUR AU - Hoffmann, Sandro Phil AU - Albert, Maximilian AU - Meier, Cedrik ID - 7484 JF - Superlattices and Microstructures SN - 0749-6036 TI - Fabrication of fully undercut ZnO-based photonic crystal membranes with 3D optical confinement VL - 97 ER - TY - JOUR AU - Weber, Nils AU - Protte, Maximilian AU - Walter, Felicitas AU - Georgi, Philip AU - Zentgraf, Thomas AU - Meier, Cedrik ID - 682 IS - 20 JF - Physical Review B SN - 2469-9950 TI - Double resonant plasmonic nanoantennas for efficient second harmonic generation in zinc oxide VL - 95 ER - TY - CONF AU - Riedl, Thomas AU - Kunnathully, Vinay AU - Karlisch, A. AU - Reuter, Dirk AU - Weber, N. AU - Meier, Cedrik AU - Schierholz, R. AU - Lindner, Jörg ID - 3988 TI - Morphology, structure and enhanced PL of molecular beam epitaxial In0.2Ga0.8As layers on nanopillar patterned GaAs ER - TY - JOUR AU - Poltavtsev, S. V. AU - Kosarev, A. N. AU - Akimov, I. A. AU - Yakovlev, D. R. AU - Sadofev, S. AU - Puls, J. AU - Hoffmann, S. P. AU - Albert, M. AU - Meier, Cedrik AU - Meier, Torsten AU - Bayer, M. ID - 7480 IS - 3 JF - Physical Review B SN - 2469-9950 TI - Time-resolved photon echoes from donor-bound excitons in ZnO epitaxial layers VL - 96 ER - TY - JOUR AU - Walter, Felicitas AU - Li, Guixin AU - Meier, Cedrik AU - Zhang, Shuang AU - Zentgraf, Thomas ID - 684 IS - 5 JF - Nano Letters SN - 1530-6984 TI - Ultrathin Nonlinear Metasurface for Optical Image Encoding VL - 17 ER - TY - JOUR AB - The electronic band structures of hexagonal ZnO and cubic ZnS, ZnSe, and ZnTe compounds are determined within hybrid-density-functional theory and quasiparticle calculations. It is found that the band-edge energies calculated on the G0W0 (Zn chalcogenides) or GW (ZnO) level of theory agree well with experiment, while fully self-consistent QSGW calculations are required for the correct description of the Zn 3d bands. The quasiparticle band structures are used to calculate the linear response and second-harmonic-generation (SHG) spectra of the Zn–VI compounds. Excitonic effects in the optical absorption are accounted for within the Bethe–Salpeter approach. The calculated spectra are discussed in the context of previous experimental data and present SHG measurements for ZnO. AU - Riefer, Arthur AU - Weber, Nils AU - Mund, Johannes AU - Yakovlev, Dmitri R. AU - Bayer, Manfred AU - Schindlmayr, Arno AU - Meier, Cedrik AU - Schmidt, Wolf Gero ID - 7481 IS - 21 JF - Journal of Physics: Condensed Matter SN - 0953-8984 TI - Zn–VI quasiparticle gaps and optical spectra from many-body calculations VL - 29 ER - TY - JOUR AU - Weber, N. AU - Hoffmann, S. P. AU - Albert, M. AU - Zentgraf, Thomas AU - Meier, Cedrik ID - 1327 IS - 10 JF - Journal of Applied Physics SN - 0021-8979 TI - Efficient frequency conversion by combined photonic–plasmonic mode coupling VL - 123 ER - TY - JOUR AU - Hoffmann, Sandro P. AU - Albert, Maximilian AU - Weber, Nils AU - Sievers, Denis AU - Förstner, Jens AU - Zentgraf, Thomas AU - Meier, Cedrik ID - 1430 JF - ACS Photonics KW - tet_topic_phc SN - 2330-4022 TI - Tailored UV Emission by Nonlinear IR Excitation from ZnO Photonic Crystal Nanocavities VL - 5 ER - TY - JOUR AU - Köthemann, Ronja AU - Weber, Nils AU - Lindner, Jörg K N AU - Meier, Cedrik ID - 12930 IS - 9 JF - Semiconductor Science and Technology SN - 0268-1242 TI - High-precision determination of silicon nanocrystals: optical spectroscopy versus electron microscopy VL - 34 ER - TY - JOUR AB - Free from phase-matching constraints, plasmonic metasurfaces have contributed significantly to the control of optical nonlinearity and enhancement of nonlinear generation efficiency by engineering subwavelength meta-atoms. However, high dissipative losses and inevitable thermal heating limit their applicability in nonlinear nanophotonics. All-dielectric metasurfaces, supporting both electric and magnetic Mie-type resonances in their nanostructures, have appeared as a promising alternative to nonlinear plasmonics. High-index dielectric nanostructures, allowing additional magnetic resonances, can induce magnetic nonlinear effects, which, along with electric nonlinearities, increase the nonlinear conversion efficiency. In addition, low dissipative losses and high damage thresholds provide an extra degree of freedom for operating at high pump intensities, resulting in a considerable enhancement of the nonlinear processes. We discuss the current state of the art in the intensely developing area of all-dielectric nonlinear nanostructures and metasurfaces, including the role of Mie modes, Fano resonances, and anapole moments for harmonic generation, wave mixing, and ultrafast optical switching. Furthermore, we review the recent progress in the nonlinear phase and wavefront control using all-dielectric metasurfaces. We discuss techniques to realize all-dielectric metasurfaces for multifunctional applications and generation of second-order nonlinear processes from complementary metal–oxide–semiconductor-compatible materials. AU - Sain, Basudeb AU - Meier, Cedrik AU - Zentgraf, Thomas ID - 8797 IS - 2 JF - Advanced Photonics SN - 2577-5421 TI - Nonlinear optics in all-dielectric nanoantennas and metasurfaces: a review VL - 1 ER - TY - JOUR AU - Vondran, J. AU - Spitzer, F. AU - Bayer, M. AU - Akimov, I. A. AU - Trautmann, Alexander AU - Reichelt, Matthias AU - Meier, Cedrik AU - Weber, N. AU - Meier, Torsten AU - André, R. AU - Mariette, H. ID - 14544 IS - 15 JF - Physical Review B SN - 2469-9950 TI - Spatially asymmetric transients of propagating exciton-polariton modes in a planar CdZnTe/CdMgTe guiding structure VL - 100 ER - TY - JOUR AU - Vondran, J. AU - Spitzer, F. AU - Bayer, M. AU - Akimov, I. A. AU - Trautmann, Alexander AU - Reichelt, Matthias AU - Meier, Cedrik AU - Weber, N. AU - Meier, Torsten AU - André, R. AU - Mariette, H. ID - 22887 IS - 15 JF - Physical Review B SN - 2469-9950 TI - Spatially asymmetric transients of propagating exciton-polariton modes in a planar CdZnTe/CdMgTe guiding structure VL - 100 ER - TY - JOUR AU - Protte, Maximilian AU - Weber, Nils AU - Golla, Christian AU - Zentgraf, Thomas AU - Meier, Cedrik ID - 9897 JF - Journal of Applied Physics SN - 0021-8979 TI - Strong nonlinear optical response from ZnO by coupled and lattice-matched nanoantennas VL - 125 ER - TY - JOUR AU - Golla, C. AU - Weber, N. AU - Meier, Cedrik ID - 9698 IS - 7 JF - Journal of Applied Physics SN - 0021-8979 TI - Zinc oxide based dielectric nanoantennas for efficient nonlinear frequency conversion VL - 125 ER - TY - JOUR AB - Plasmonic nanoantennas for visible and infrared radiation strongly improve the interaction of light with the matter on the nanoscale due to their strong near-field enhancement. In this study, we investigate a double-resonant plasmonic nanoantenna, which makes use of plasmonic field enhancement, enhanced outcoupling of second harmonic light, and resonant lattice effects. Using this design, we demonstrate how the efficiency of second harmonic generation can be increased significantly by fully embedding the nanoantennas into nonlinear dielectric material ZnO, instead of placing them on the surface. Investigating two different processes, we found that the best fabrication route is embedding the gold nanoantennas in ZnO using an MBE overgrowth process where a thin ZnO layer was deposited on nanoantennas fabricated on a ZnO substrate. In addition, second harmonic generation measurements show that the embedding leads to an enhancement compared to the emission of nanoantennas placed on the ZnO substrate surface. These promising results facilitate further research to determine the influence of the periodicity of the nanoantenna arrangement of the resulting SHG signal. AU - Volmert, Ruth AU - Weber, Nils AU - Meier, Cedrik ID - 20644 IS - 4 JF - Journal of Applied Physics SN - 0021-8979 TI - Nanoantennas embedded in zinc oxide for second harmonic generation enhancement VL - 128 ER - TY - JOUR AB - Nonlinear Pancharatnam–Berry phase metasurfaces facilitate the nontrivial phase modulation for frequency conversion processes by leveraging photon‐spin dependent nonlinear geometric‐phases. However, plasmonic metasurfaces show some severe limitation for nonlinear frequency conversion due to the intrinsic high ohmic loss and low damage threshold of plasmonic nanostructures. Here, the nonlinear geometric‐phases associated with the third‐harmonic generation process occurring in all‐dielectric metasurfaces is studied systematically, which are composed of silicon nanofins with different in‐plane rotational symmetries. It is found that the wave coupling among different field components of the resonant fundamental field gives rise to the appearance of different nonlinear geometric‐phases of the generated third‐harmonic signals. The experimental observations of the nonlinear beam steering and nonlinear holography realized in this work by all‐dielectric geometric‐phase metasurfaces are well explained with the developed theory. This work offers a new physical picture to understand the nonlinear optical process occurring at nanoscale dielectric resonators and will help in the design of nonlinear metasurfaces with tailored phase properties. AU - Liu, Bingyi AU - Sain, Basudeb AU - Reineke, Bernhard AU - Zhao, Ruizhe AU - Meier, Cedrik AU - Huang, Lingling AU - Jiang, Yongyuan AU - Zentgraf, Thomas ID - 16197 IS - 9 JF - Advanced Optical Materials SN - 2195-1071 TI - Nonlinear Wavefront Control by Geometric-Phase Dielectric Metasurfaces: Influence of Mode Field and Rotational Symmetry VL - 8 ER - TY - CONF AB - We fabricate silicon tapers to increase the mode overlap of superconducting detectors on Ti:LiNbO3 waveguides. Mode images show a reduction in mode size from 6 µm to 2 µm FWHM, agreeing with beam propagation simulations. AU - Protte, Maximilian AU - Ebers, Lena AU - Hammer, Manfred AU - Höpker, Jan Philipp AU - Albert, Maximilian AU - Quiring, Viktor AU - Meier, Cedrik AU - Förstner, Jens AU - Silberhorn, Christine AU - Bartley, Tim ID - 21719 KW - tet_topic_waveguide SN - 9781943580811 T2 - OSA Quantum 2.0 Conference TI - Towards Semiconductor-Superconductor-Crystal Hybrid Integration for Quantum Photonics ER - TY - JOUR AU - Albert, M. AU - Golla, C. AU - Meier, Cedrik ID - 20900 JF - Journal of Crystal Growth SN - 0022-0248 TI - Optical in-situ temperature management for high-quality ZnO molecular beam epitaxy VL - 557 ER - TY - JOUR AB - In this paper, silicon oxynitride films (SiON) grown by plasma-enhanced chemical vapor deposition are investigated. As precursor gases silane (SiH4), nitrous oxide (N2O), nitrogen (N2) and ammonia (NH3) are used with different compositions. We find that for achieving high nitrogen content adding ammonia to the precursor mix is most efficient. Moreover, we investigate the balance between adsorption and desorption processes during film growth by investigating the film growth rate as a function of the substrate temperature. From these data we are able to determine an effective activation energy for the film growth, corresponding to the difference between adsorption and desorption energy. Finally, we have thoroughly investigated the optical properties of the films using spectroscopic ellipsometry. From these measurements, we suggest a parametrized model for the refractive index and extinction coefficient in a wide range of compositions based on a Cauchy- and a Lorentz-fit. AU - Aschwanden, R. AU - Köthemann, R. AU - Albert, M. AU - Golla, C. AU - Meier, Cedrik ID - 23815 JF - Thin Solid Films SN - 0040-6090 TI - Optical properties of silicon oxynitride films grown by plasma-enhanced chemical vapor deposition VL - 736 ER - TY - JOUR AU - Mund, Johannes AU - Yakovlev, Dmitri R. AU - Sadofev, Sergey AU - Meier, Cedrik AU - Bayer, Manfred ID - 22214 JF - Physical Review B SN - 2469-9950 TI - Second harmonic generation on excitons in ZnO/(Zn,Mg)O quantum wells with built-in electric fields VL - 103 ER - TY - JOUR AB - GaAs-(111)-nanostructures exhibiting second harmonic generation are new building blocks in nonlinear optics. Such structures can be fabricated through epitaxial lift-off using selective etching of Al-containing layers and subsequent transfer to glass substrates. Herein, the selective etching of (111)B-oriented AlxGa1−xAs sacrificial layers (10–50 nm thick) with different aluminum concentrations (x = 0.5–1.0) in 10\% hydrofluoric acid is investigated and compared with standard (100)-oriented structures. The thinner the sacrificial layer and the lower the aluminum content, the lower the lateral etch rate. For both orientations, the lateral etch rates are in the same order of magnitude, but some quantitative differences exist. Furthermore, the epitaxial lift-off, the transfer, and the nanopatterning of thin (111)B-oriented GaAs membranes are demonstrated. Atomic force microscopy and high-resolution X-ray diffraction measurements reveal the high structural quality of the transferred GaAs-(111) films. AU - Henksmeier, Tobias AU - Eppinger, Martin AU - Reineke, Bernhard AU - Zentgraf, Thomas AU - Meier, Cedrik AU - Reuter, Dirk ID - 20592 IS - 3 JF - physica status solidi (a) KW - epitaxial lift-off KW - GaAs/AlxGa1−xAs heterostructures KW - selective etching TI - Selective Etching of (111)B-Oriented AlxGa1−xAs-Layers for Epitaxial Lift-Off VL - 218 ER - TY - JOUR AU - Widhalm, Alex AU - Golla, Christian AU - Weber, Nils AU - Mackwitz, Peter AU - Zrenner, Artur AU - Meier, Cedrik ID - 29716 IS - 4 JF - Optics Express KW - Atomic and Molecular Physics KW - and Optics SN - 1094-4087 TI - Electric-field-induced second harmonic generation in silicon dioxide VL - 30 ER - TY - JOUR AB - Lithium niobate on insulator (LNOI) has a great potential for photonic integrated circuits, providing substantial versatility in design of various integrated components. To properly use these components in the implementation of different quantum protocols, photons with different properties are required. In this paper, we theoretically demonstrate a flexible source of correlated photons built on the LNOI waveguide of a special geometry. This source is based on the parametric down-conversion (PDC) process, in which the signal and idler photons are generated at the telecom wavelength and have different spatial profiles and polarizations, but the same group velocities. Distinguishability in polarizations and spatial profiles facilitates the routing and manipulating individual photons, while the equality of their group velocities leads to the absence of temporal walk-off between photons. We show how the spectral properties of the generated photons and the number of their frequency modes can be controlled depending on the pump characteristics and the waveguide length. Finally, we discuss special regimes, in which narrowband light with strong frequency correlations and polarization-entangled Bell states are generated at the telecom wavelength. AU - Ebers, Lena AU - Ferreri, Alessandro AU - Hammer, Manfred AU - Albert, Maximilian AU - Meier, Cedrik AU - Förstner, Jens AU - Sharapova, Polina R. ID - 30210 JF - Journal of Physics: Photonics KW - tet_topic_waveguide SN - 2515-7647 TI - Flexible source of correlated photons based on LNOI rib waveguides VL - 4 ER - TY - JOUR AB - The free exciton transition (near-band-edge emission, NBE) of ZnO at ≈388 nm can be strongly enhanced and even stimulated by an underlying photonic structure. 1D Photonic crystals, so-called distributed Bragg reflectors, are utilized to suppress the deep-level emission of ZnO (DLE, ≈500–530 nm). The reflector stacks are fabricated in a layer-by-layer procedure by wet-chemical synthesis. They consist of low-ε porous SiO2 layers and high-ε TiO2 layers. Varying the thickness of the SiO2 layers allows tuning the optical bandgap in a wide range between ≈420 and 800 nm. A ZnO layer is deposited on top of the reflector stacks by sol–gel synthesis. The spontaneous photoluminescence (PL) emission of the ZnO film is modulated by the photonic structure. When the optical bandgap of the reflector is in resonance with the deep-level emission of ZnO (DLE, ≈500–530 nm), then this defect-related emission mode is suppressed. Strong NBE emission is observed even when the ZnO layer does not show any NBE emission (due to low crystallinity) in the absence of the photonic structure. With this cost-efficient synthesis method, emitters for, e.g., luminescent gas sensors can be fabricated. AU - Kothe, Linda AU - Albert, Maximilian AU - Meier, Cedrik AU - Wagner, Thorsten AU - Tiemann, Michael ID - 29790 JF - Advanced Materials Interfaces KW - Mechanical Engineering KW - Mechanics of Materials SN - 2196-7350 TI - Stimulation and Enhancement of Near‐Band‐Edge Emission in Zinc Oxide by Distributed Bragg Reflectors ER - TY - JOUR AB - We present strong enhancement of third harmonic generation in an amorphous silicon metasurface consisting of elliptical nano resonators. We show that this enhancement originates from a new type of multi-mode Fano mechanism. These ‘Super-Fano’ resonances are investigated numerically in great detail using full-wave simulations. The theoretically predicted behavior of the metasurface is experimentally verified by linear and nonlinear transmission spectroscopy. Moreover, quantitative nonlinear measurements are performed, in which an absolute conversion efficiency as high as ηmax ≈ 2.8 × 10−7 a peak power intensity of 1.2 GW cm−2 is found. Compared to an unpatterned silicon film of the same thickness amplification factors of up to ~900 are demonstrated. Our results pave the way to exploiting a strong Fano-type multi-mode coupling in metasurfaces for high THG in potential applications. AU - Hähnel, David AU - Golla, Christian AU - Albert, Maximilian AU - Zentgraf, Thomas AU - Myroshnychenko, Viktor AU - Förstner, Jens AU - Meier, Cedrik ID - 44097 IS - 1 JF - Light: Science & Applications KW - tet_topic_meta SN - 2047-7538 TI - A multi-mode super-fano mechanism for enhanced third harmonic generation in silicon metasurfaces VL - 12 ER -