Many-body effects on optical carrier cooling in intrinsic semiconductors at low lattice temperatures

Abstract

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Cryogenic optical refrigeration

“…This effect limits the possibility of laser cooling of rare-earth-doped solids at temperatures below about 50 K. In principle this limit does not exist for laser cooling of semiconductors whose electrons and holes are indistinguishable and which thus obey Fermi-Dirac statistics. The feasibility of laser cooling in semiconductors has been extensively investigated both theoretically [17,[51][52][53][54][55][56][57][58][59][60][61] and experimentally [61][62][63][64][65][66][67][68][69]; however, no net temperature reduction has been observed yet. This failure is due to stringent purity requirements, complications associated with inefficient light extraction from the high-refractive-index substrate (η e < 0.2 for nearly index-matched dome [17,66]), and many-body effects such as a carrier-density-dependent quantum efficiency.…”

Laser cooling of solids

“…Laser cooling of semiconductors has been examined theoretically [15,44,45,[47][48][49][50][51][52] as well as in experimental studies [46,[53][54][55][56]. A feasibility study by the authors outlined the conditions for net cooling based on fundamental material properties and light management [15].…”

Quasiperiodicity and suppression of multistability in nonlinear dynamical systems

“…Here, the statistical resistive force [134] has been approximated by the momentum relaxation rate. Based on the energy-balance equation, one can show [135] that E e (t) satisfies the following dynamical equation…”