Nonlinear behaviour of the resonance fluorescence from excitons in quantum wells

Transition from excitonic to plasma emission from localized electron‐hole pair states in GaAs‐AlGaAs quantum wells

“…This concept has been extended to the dielectric response in semiconductors in order to describe the phase and amplitude of light propagating through semiconductor heterostructures [2,3] for excitations well below the Mott transition of excitons. In recent experiments [4,5] the resonant Rayleigh scattering from localized electron-hole (eh) pair states in GaAs-AlGaAs quantum wells has been investigated, showing at high excitation the transition from excitonic to plasma emission over a wide range of the density of excited carriers and temperatures. Adjusting the spectral position of the exciting laser at the peak of the exciton line at low excitation, first of all a decrease of the emission with increasing excitation is observed.…”

“…This approximation fails (see [6] for bulk ZnSe) for excitations around the Mott transition of excitons, rather the influence of many-body effects has to be considered, which change both the dispersion and the chemical potentials of carriers for fixed density and temperature. In this paper we present a detailed theoretical explanation of experimental results for the emission of localized ex- citons in GaAs-GaAlAs quantum wells [4,5], investigating the influence of dynamical screening both on the oneparticle properties of carriers and on the whole spectrum of electron-hole (eh) pair states, ranging from 1s-and 2s-excitonic states up to the band edge. In particular, we explain the change of the shift of the exciton energy from higher energies at temperatures below T < 10 K to lower energies at T > 10 K. For the description of many-body effects between carriers in the EHP of excited quantum wells semiconductor we refer to [12], where we have investigated the influence of quantum kinetic effects on the linear optical response.…”

“…(9) corresponds to an effective Wannier equation for excitons, extended by many-body effects, which describes the whole spectrum of two-particle states. In this paper we focus on the details of the shift of the 1s-exciton state, in order to explain the behavior of the emission of the quantum wells observed in the experiment (see [4,5]. Generally, the exciton energy remains nearly constant with increasing excitation.…”

Intense laser field effect on the interband absorption in differently shaped near-surface quantum wells

“…The optical absorption associated with the excitons in semiconductor quantum wells (QWs) have been the subject of a considerable amount of work for the reason that the exciton binding energy and oscillator strength in QWs are considerably enhanced due to quantum confinement effect [1][2][3][4][5]. In recent years, InGaAs/GaAs QW structures have attracted much interest because of their promising applications in optoelectronic and microelectronic devices [6][7][8][9].…”

Mott transition of excitons in GaAs-GaAlAs quantum wells

“…Recent experiments [41] have shown the transition from excitonic to plasma emission in the resonance fluorescence from localized excitons in quantum wells. Working with a tunable continuous wave laser with a spectral width much smaller than the exciton binding energy, one is able to detect the dielectric response over the whole spectral range between the 1s exciton and the band edge and open a direct comparison with results of the semiconductor Bloch equations.…”