相关论文: Excitonic Photoluminescence in Semiconductor Quant…
The dynamics of exciton and electron-hole plasma populations is studied via time-resolved photoluminescence after nonresonant excitation. By comparing the peak emission at the exciton resonance with the emission of the continuum, it is…
Excitons in semiconductors may form correlated phases at low temperatures. We report the observation of an exciton liquid in GaAs/AlGaAs coupled quantum wells. Above a critical density and below a critical temperature the photogenerated…
We show that a quasi-two dimensional condensate of optically active excitons emits coherent light even in the absence of population inversion. This allows an unambiguous and clear experimental detection of the condensed phase. We prove…
A fully microscopic theory for the spontaneous emission from semiconductors is discussed. The theory is evaluated for a quantum-well system and the role of excitonic and unbound electron-hole-pair contributions to the emission is analyzed.…
When electron-hole pairs are excited in a semiconductor, it is a priori not clear if they form a fermionic plasma of unbound particles or a bosonic exciton gas. Usually, the exciton phase is associated with low temperatures. In atomically…
Mostly optical spectroscopies are used to investigate existence of excitons, Mott transitions and other exquisite excitonic condensed phases of matter. On the other hand, electrical signatures of excitons are hardly explored. Here we…
We have closely examined the emission spectrum at the heavy-hole exciton resonance in a high-quality GaAs multi-quantum well (MQW) sample using picosecond excitation-correlation photoluminescence (ECPL) spectroscopy. Dynamics of the ECPL…
Bound electron-hole excitonic states are generally not expected to form with charges of negative effective mass. We identify such excitons in a single layer of the semiconductor WSe2, where they give rise to narrow-band upconverted…
Photoluminescence spectra measured on a type-II GaSb/GaAs quantum dot ensemble at high excitation power indicate a Mott transition from the low density state comprising of spatially-indirect excitons to a high density electron-plasma state.…
We exploit the influence of the Coulomb interaction between electrons and holes on the electron spin relaxation in a (110)-GaAs quantum well to unveil excitonic signatures within the many particle electron-hole system. The temperature…
The negatively charged quasi-two-dimensional exciton ($X^-$) is studied numerically in the presence of a uniform B-field and various in-plane confinements. The corresponding photoluminescence (PL) spectra, including shakeup processes, are…
We study the fluorescence light emitted from GaAs excitons in semiconductor quantum wells. The excitons are modeled as interacting bosons. By combining quantum optical methods for the excitonic emission spectrum with many particle…
We theoretically investigate the scenario of a semiconductor quantum well in a microcavity, where the band structure is arranged such that optically excited electron-hole pairs cannot form Coulomb-bound excitonic states. However, it is…
An excitonic insulator phase is expected to arise from the spontaneous formation of electron-hole pairs (excitons) in semiconductors where the exciton binding energy exceeds the size of the electronic band gap. At low temperature, these…
There have been extensive experimental search for possible exciton superfluid in semiconductor electron-hole bilayer systems below liquid Helium temperature. However, exciton superfluid are meta-stable and will eventually decay through…
Semiconductors in all dimensionalities ranging from 0D quantum dots and molecules to 3D bulk crystals support bound electron-hole pair quasiparticles termed as excitons. Over the past two decades, the emergence of a variety of…
Resonant optical excitation of few-level quantum systems enables coherent quantum control, resonance fluorescence, and direct characterization of dephasing mechanisms. Experimental demonstrations have been achieved in a variety of atomic…
We investigate resonant photoluminescence arising from incompressible quantum liquids formed in two-dimensional electron systems. We demonstrate that, for excitons composed of a photoexcited electron occupying the upper spin sublevel of the…
Coherence transfer is a multi-disciplinary topic of interest, including chemistry, biology and physics. In quantum technologies, achieving non-local coherent coupling between solid-state qubits is of the utmost importance. Here, we…
We consider a line-shape of magnetoexciton photoluminescence from quantum wells when the disorder is sufficiently small. In this case the phonon-assisted optical transitions become important for the line formation. We study both inter-band…