A5056468308- Cold Atom Physics and Bose-Einstein Condensates
- Semiconductor Quantum Structures and Devices
- Strong Light-Matter Interactions
- 2D Materials and Applications
- Advanced Thermodynamics and Statistical Mechanics
- Plasmonic and Surface Plasmon Research
- Spectroscopy and Quantum Chemical Studies
- Perovskite Materials and Applications
- Photonic Crystals and Applications
- Chalcogenide Semiconductor Thin Films
- Nonlinear Photonic Systems
- Plasma Diagnostics and Applications
- Quantum optics and atomic interactions
- Quantum, superfluid, helium dynamics
- Algebraic structures and combinatorial models
- Gold and Silver Nanoparticles Synthesis and Applications
- Optical Coatings and Gratings
- Nonlinear Waves and Solitons
- Particle accelerators and beam dynamics
- Optical properties and cooling technologies in crystalline materials
- Mass Spectrometry Techniques and Applications
- Quantum and electron transport phenomena
Weizmann Institute of Science
2018-2024
Munich Center for Quantum Science and Technology
2024
Ludwig-Maximilians-Universität München
2024
Center for NanoScience
2024
Indian Institute of Science Education and Research Kolkata
2017
Laser modulation spectroscopy on a MoSe${}_{2}$/WS${}_{2}$ heterostructure shows an intricate interplay of both intra- and interlayer moir\'e excitons allows to determine unambiguously the nature observed optical resonances.
Fano resonance is observed in a wide range of micro- and nano-optical systems has been subject intensive investigations due to its numerous potential applications. Methods that can control or modulate by tuning some experimentally accessible parameters are highly desirable for realistic Here we present simple yet elegant approach using the Mueller matrix formalism controlling interference effect engineering resulting asymmetric spectral line shape an anisotropic optical system. The founded...
We study the exciton gas-liquid transition in GaAs/AlGaAs coupled quantum wells. Below a critical temperature, Tc=4.8K, and above threshold laser power density system undergoes phase into liquid state. determine temperature diagram over range 0.1 to 4.8K. find that latent heat increases linearly with at T<1.1K, similarly Bose Einstein condensate transition, becomes constant 1.1<T<4.8K. Resonant Rayleigh scattering measurements reveal disorder sample is strongly suppressed diffusion...
We show that a Bose-Einstein condensate consisting of dark excitons forms in GaAs coupled quantum wells at low temperatures. find the extends over hundreds micrometers, well beyond optical excitation region, and is limited only by boundaries mesa. density determined spin-flipping collisions among excitons, which convert into bright ones. The suppression this process temperature yields buildup, manifested as temperature-dependent blueshift exciton emission line. Measurements under an in-plane...
Moir\'e materials provide a unique platform for studies of correlated many-body physics the Fermi-Hubbard model on triangular spin-charge lattices. Bilayer Hubbard models are particular significance with regard to Mott insulating states and their relation unconventional superconductivity, yet experimental implementation in moir\'e systems has so far remained elusive. Here, we demonstrate realization staggered bilayer lattice electrons an antiparallel MoSe$_{2}$/WS$_{2}$ heterostructure. The...
We study the interaction of a dark exciton Bose-Einstein condensate with nuclei in GaAs/AlGaAs coupled quantum wells and find clear evidence for nuclear polarization buildup that accompanies appearance condensate. show are polarized throughout mesa area, extending to regions which far away from photoexcitation persisting seconds after excitation is switched off. Photoluminescence measurements presence RF radiation reveal hyperfine between electron spins enhanced by two orders magnitude....
We study the interaction of a dark exciton Bose-Einstein condensate with nuclei in gallium arsenide/aluminum arsenide coupled quantum wells and find clear evidence for nuclear polarization buildup that accompanies appearance condensate. show are polarized throughout mesa area, extending to regions far away from photoexcitation area persisting seconds after excitation is switched off. Photoluminescence measurements presence radio frequency radiation reveal hyperfine between electron spins...
Semiconductor moir\'e heterostructures exhibit rich correlation-induced many-body phenomena with signatures of emergent magnetism, Mott insulating states or generalized Wigner crystals observed in optical spectroscopy by probing intralayer excitons. However, as the staggered band alignment underlying WSe$_2$/WS$_2$ heterobilayer system separates photoexcited electrons and holes to form lowest-energy interlayer excitons, direct access interactions between correlated charge ground state...
We study experimentally and theoretically the hybridization among intralayer interlayer moir\'e excitons in a MoSe$_2$/WS$_2$ heterostructure with antiparallel alignment. Using dual-gate device cryogenic white light reflectance narrow-band laser modulation spectroscopy, we subject heterostack to perpendicular electric field, monitor field-induced dispersion of exciton states, induce cross-over from type I II band Moreover, employ magnetic fields map out dependence corresponding Land\'e...