Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:cond-mat/0408453

Direct Optical Excitation of Quantum-Degenerate Exciton States in Semiconductors

M. Kira, S. W. Koch, G. Khitrova, H. M. Gibbs

Published Aug 20, 2004• 0 citations
arXivHTMLPDF

Abstract

Quantum electrodynamic calculations predict that truly incoherent light can be used to efficiently generate quantum-degenerate exciton population states. Resonant incoherent excitation directly converts photons into excitons with vanishing center of mass momentum. The populated exciton state possesses long-range order, is very stable against perturbations, and should be observable via its unusual directional and density dependence in luminescence measurements.

DOI
10.48550/arxiv.cond-mat/0408453

Related papers

Photoluminescence and quantum-degenerate exciton states in semiconductors

M. Kira, S. W. Koch

Quantum-electrodynamic calculations predict that truly incoherent light can be used to efficiently generate quantum-degenerate exciton population states. Resonant incoherent excitation directly converts photons into excitons with vanishing center of mass momentum. The populated exciton state possesses long-range order, is very stable against perturbations, and should be observable via its unusual directional and density dependence in luminescence measurements.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Dec 28, 2005•0 citations

Quantum-optical spectroscopy of semiconductors

M. Kira, S. W. Koch

The microscopic foundation of quantum-optical spectroscopy is presented. It is proposed to use this technique to generate and detect quasiparticle states in semiconductors whose quantum-statistical properties are governed by that of the exciting light. While resonant classical excitation induces an optical interband polarization, low-intensity quantum excitation directly seeds a quantum-degenerate exciton state which is characterized by long-range order, anomalous reduction of Coulomb and phonon scattering, as well as strongly enhanced and directional quantum emission.

Physical Review A•Jan 18, 2006•124 citations

Quantum optics beyond quantum-degenerate excitons

M. Kira

Conceptually, a single-mode laser light may be perceived as a quantum-degenerate state because all of its photons occupy one and the same light-mode state. One can utilize this property in direct-gap semiconductor in order to excite, e.g., quantum-degenerate excitons that are Coulomb-bound electronhole pairs. For example, if a classical laser resonant with an exciton resonance, the resulting excitation injects a quantum-degenerate state of coherent excitons. This process is fully explained by the semiconductor Bloch equations [1] where the quantum-degenerate coherent excitons are simply described by a polarization. One can rigorously generalize [2] this state-injection concept to realize quantum-optical spectroscopy beyond simple excitons because also laser’s quantum fluctuations are injected as such to the quantumdegenerate electron-hole pairs, before the onset of Coulomb and phonon-induced scattering. More explicitly, the quantum aspects of a single-mode pump laser are defined by a boson operator B while the Coulomb-bound electron-hole pairs are described by an exciton operator X that is bosonic only approximately. When the pump laser has quantum-optical correlations †J K

•Jan 1, 2013•0 citations

Generation of coherent quantum light from a single impurity-bound exciton

Yuxi Jiang, Christine Falter, Robert M. Pettit +6 more

Impurity-bound excitons in II-VI semiconductors are promising optically active solid-state spin qubits that combine exceptional optical quantum efficiency with a low-noise spin environment. Previous studies on single impurities in these materials relied on incoherent optical excitation to generate photons. However, many quantum applications require resonant driving of quantum emitters to precisely control optical transitions and maintain coherence of the emission. Here, we demonstrate coherent optical emission of quantum light from a resonantly driven single impurity-bound exciton in ZnSe. The resonantly driven emitter exhibits bright quantum emission that preserves the phase of the resonant drive. It also features an intensity-dependent nonlinear phase shift at low photon numbers. Resonant excitation enables direct measurement of the Debye-Waller factor, determined to be 0.94, which indicates high efficiency emission to the zero-phonon line. Time-resolved resonance fluorescence measurements reveal a fast optically driven ionization process, along with a slower spontaneous ionization process having a lifetime of 21 μ s due to charge tunneling from the impurity. These results pave the way for coherent generation of quantum light and low-photon-number nonlinear optics through resonant excitation of impurity-bound excitons.

arXiv:2412.01677•npj Quantum Information•Aug 13, 2026•0 citations

Ultrafast secondary radiation of excitons in quantum wells: The transition from the coherent to the incoherent regime

Stefan Haacke, Gary R. Hayes, Robert Anthony Taylor +2 more

Coherent Rayleigh scattering and incoherent luminescence are studied by femtosecond upconversion under resonant excitation as a function of exciton density in GaAs quantum wells. Comparing samples with different well widths allows to establish the relation between inhomogeneous broadening and the shape of resonant Rayleigh scattering. We find an excellent agreement between experiment and a classical model. In samples with moderate inhomogeneous broadening we provide evidence for the transition from coherent to incoherent emission. The comparison with excitonic dephasing times T2 obtained from four-wave-mixing experiments demonstrates that the incoherent exciton population rises within T2/2, at any exciton density when changed by more than an orders of magnitude. The experimental results confirm very clearly the concept predicting that the coherent polarization made up by localized excitons decays into an incoherent exciton population under conservation of the number of excited quanta.

Radiative Processes and Dephasing in Semiconductors•Jan 1, 1998•0 citations

Nonlinear-optical properties of biexcitons

Izo I. Abram

The strong optical nonlinearity of biexcitons in semiconductors necessitates a nonperturbative calculation of the nonlinear-optical susceptibility of the semiconductor and of the propagation equation of the light wave. Such calculations are possible for all light-beam geometries within a simple model in which excitons and biexcitons are treated quantum mechanically as bosons, with no reference to their internal structure. This simple model can account for most experimental observations, while when dephasing and population effects are considered it predicts the appearance of a dephasing-induced extra resonance analogous to that observed in gases or molecular crystals.

Journal of the Optical Society of America B•Jul 1, 1985•14 citations
Quantum electrodynamic calculations predict that truly incoherent light can be used to efficiently generate quantum-degenerate exciton population states. Resonant incoherent excitation directly converts photons into excitons with vanishing center of mass momentum. The populated exciton state possesses long-range order, is very stable against perturbations, and should be observable via its unusual directional and density dependence in luminescence measurements.
The microscopic foundation of quantum-optical spectroscopy is presented. It is proposed to use this technique to generate and detect quasiparticle states in semiconductors whose quantum-statistical properties are governed by that of the exciting light. While resonant classical excitation induces an optical interband polarization, low-intensity quantum excitation directly seeds a quantum-degenerate exciton state which is characterized by long-range order, anomalous reduction of Coulomb and phonon scattering, as well as strongly enhanced and directional quantum emission.
Conceptually, a single-mode laser light may be perceived as a quantum-degenerate state because all of its photons occupy one and the same light-mode state. One can utilize this property in direct-gap semiconductor in order to excite, e.g., quantum-degenerate excitons that are Coulomb-bound electronhole pairs. For example, if a classical laser resonant with an exciton resonance, the resulting excitation injects a quantum-degenerate state of coherent excitons. This process is fully explained by the semiconductor Bloch equations [1] where the quantum-degenerate coherent excitons are simply described by a polarization. One can rigorously generalize [2] this state-injection concept to realize quantum-optical spectroscopy beyond simple excitons because also laser’s quantum fluctuations are injected as such to the quantumdegenerate electron-hole pairs, before the onset of Coulomb and phonon-induced scattering. More explicitly, the quantum aspects of a single-mode pump laser are defined by a boson operator B while the Coulomb-bound electron-hole pairs are described by an exciton operator X that is bosonic only approximately. When the pump laser has quantum-optical correlations †J K
Impurity-bound excitons in II-VI semiconductors are promising optically active solid-state spin qubits that combine exceptional optical quantum efficiency with a low-noise spin environment. Previous studies on single impurities in these materials relied on incoherent optical excitation to generate photons. However, many quantum applications require resonant driving of quantum emitters to precisely control optical transitions and maintain coherence of the emission. Here, we demonstrate coherent optical emission of quantum light from a resonantly driven single impurity-bound exciton in ZnSe. The resonantly driven emitter exhibits bright quantum emission that preserves the phase of the resonant drive. It also features an intensity-dependent nonlinear phase shift at low photon numbers. Resonant excitation enables direct measurement of the Debye-Waller factor, determined to be 0.94, which indicates high efficiency emission to the zero-phonon line. Time-resolved resonance fluorescence measurements reveal a fast optically driven ionization process, along with a slower spontaneous ionization process having a lifetime of 21 μ s due to charge tunneling from the impurity. These results pave the way for coherent generation of quantum light and low-photon-number nonlinear optics through resonant excitation of impurity-bound excitons.
Coherent Rayleigh scattering and incoherent luminescence are studied by femtosecond upconversion under resonant excitation as a function of exciton density in GaAs quantum wells. Comparing samples with different well widths allows to establish the relation between inhomogeneous broadening and the shape of resonant Rayleigh scattering. We find an excellent agreement between experiment and a classical model. In samples with moderate inhomogeneous broadening we provide evidence for the transition from coherent to incoherent emission. The comparison with excitonic dephasing times T2 obtained from four-wave-mixing experiments demonstrates that the incoherent exciton population rises within T2/2, at any exciton density when changed by more than an orders of magnitude. The experimental results confirm very clearly the concept predicting that the coherent polarization made up by localized excitons decays into an incoherent exciton population under conservation of the number of excited quanta.
The strong optical nonlinearity of biexcitons in semiconductors necessitates a nonperturbative calculation of the nonlinear-optical susceptibility of the semiconductor and of the propagation equation of the light wave. Such calculations are possible for all light-beam geometries within a simple model in which excitons and biexcitons are treated quantum mechanically as bosons, with no reference to their internal structure. This simple model can account for most experimental observations, while when dephasing and population effects are considered it predicts the appearance of a dephasing-induced extra resonance analogous to that observed in gases or molecular crystals.