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arXiv · 1312.4070

Fermi-Edge Superfluorescence from a Quantum-Degenerate Electron-Hole Gas

J. -H. Kim·G. T. Noe·S. A. McGill·Y. Wang·A. K. Wojcik·A. A. Belyanin·J. Kono
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Abstract

We report on the observation of spontaneous bursts of coherent radiation from a quantum-degenerate gas of nonequilibrium electron-hole pairs in semiconductor quantum wells. Unlike typical spontaneous emission from semiconductors, which occurs at the band edge, the observed emission occurs at the quasi-Fermi edge of the carrier distribution. As the carriers are consumed by recombination, the quasi-Fermi energy goes down toward the band edge, and we observe a continuously red-shifting streak. We interpret this emission as cooperative spontaneous recombination of electron-hole pairs, or superfluorescence, which is enhanced by Coulomb interactions near the Fermi edge. This novel many-body enhancement allows the magnitude of the spontaneously developed macroscopic polarization to exceed the maximum value for ordinary superfluorescence, making electron-hole superfluorescence even more "super" than atomic superfluorescence.

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J. -H. Kim, G. T. Noe, S. A. McGill, Y. Wang, A. K. Wojcik, A. A. Belyanin, J. Kono. 2013-12-14. Fermi-Edge Superfluorescence from a Quantum-Degenerate Electron-Hole Gas. https://doi.org/10.1038/srep03283

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