相关论文: Collective Excitations in Asymmetric Parabolic Qua…
We point out a novel manifestation of many-body correlations in the linear optical response of electrons confined in a quantum well. Namely, we demonstrate that along with conventional absorption peak at frequency close to intersubband…
We study the collective excitations and inelastic light scattering cross-section of an electron gas confined in a GaAs/AlGaAs coaxial quantum well. These system can be engineered in a core-multi-shell nanowire and inherit the hexagonal…
Measurements and a theoretical interpretation of the excitation spectrum of a two-electron quantum dot fabricated on a parabolic Ga[Al]As quantum well are reported. Experimentally, excited states are found beyond the well-known lowest…
We studied, theoretically, the optical absorption spectra for a slightly asymmetric double quantum well (DQW), in the presence of electric and magnetic fields. Recent experimental results for a 10.18/3.82/9.61 nm GaAs Al(_{.33}…
Recent photoabsorption measurements have revealed a rich fine structure in the collective charge-density excitation spectrum of few-electron quantum dots in the presence of magnetic fields. We have performed systematic computational studies…
We studied theoretically the excitonic energy levels and the optical absorption spectra for double quantum wells, both symmetric and asymmetric, in the presece of an homogeneous magnetic field. Within the effective mass approach, we…
We report the first terahertz study of the intra-excitonic 1s-2p transition at high excitation densities in GaAs/AlGaAs quantum wells. A strong shift, broadening, and ultimately the disappearance of this resonance occurs with increasing…
In this work, the linear absorption spectra for periodic arrays of GaAs-GaAsAl quantum wells with different thicknesses, inside electromagnetic wave has been studied. The eigen energies and eigen functions are calculated by solving the…
We consider theoretically magnetic dipole mechanism of the IR-light absorption at intersubband transitions in wide-gap quantum wells (QW). In contrast to the electric dipole resonance, discussed mechanism manifests in the interaction with…
We present microscopic calculations of the absorption spectra for GaN/Al(x)Ga(1-x)N quantum well systems. Whereas the quantum well structures with the parabolic law of dispersion exhibit the usual bleaching of an exciton resonance without…
We use time-dependent (current) density functional theory to study collective transitions between the two lowest subbands in GaAs/AlGaAs quantum wells. We focus on two systems where experimental results are available: a wide single and a…
We study an asymmetric double InGaAs quantum well using optical two-dimensional coherent spectroscopy. The collection of zero-quantum, one-quantum, and two-quantum two-dimensional spectra provides a unique and comprehensive picture of the…
The spectra of plasma and magnetoplasma excitations in a two-dimensional system of anisotropic heavy fermions were investigated for the first time. The spectrum of microwave absorption by disk-like samples of stressed AlAs quantum wells at…
Oscillations of the real component of AC conductivity $\sigma_1$ in a magnetic field were measured in the n-AlGaAs/GaAs structure with a wide (75 nm) quantum well by contactless acoustic methods at $T$=(20-500)~mK. In a wide quantum well,…
We present a systematic theoretical study of the multi-photon nonlinear optical absorption properties of a $\text{GaAs/A}{{\text{l}}_{x}}\text{G}{{\text{a}}_{1-x}}\text{As}$ based quantum well (QW) structure with Morse confinement potential…
We present a theory for the intersubband absorption including electronic ground state correlations in a doped GaAs/Al_{35}Ga_{65}As quantum well system. Focusing on the influence of the Coulomb interaction among the carriers at low…
The collective charge-excitation spectrum of a double quantum well system in a strong magnetic field is obtained within the random phase approximation. Correction to the spectrum coming from the finiteness of the magnetic field is…
Using the time-dependent-local-density-approximation (TDLDA) within a self-consistent linear response theory, we calculate the elementary excitation energies and the associated inelastic light-scattering spectra of a strongly coupled…
We theoretically study the coherent nonlinear response of electrons confined in semiconductor quantum wells under the effect of an electromagnetic radiation close to resonance with an intersubband transition. Our approach is based on the…
Intersubband absorption in modulation-doped quantum wells is usually appropriately described as a collective excitation of the confined two-dimensional electron gas. At sufficiently low electron density and low temperatures, however, the…