Room-Temperature Polariton Lasing in Semiconductor Microcavities

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Abstract

We observe a room-temperature low-threshold transition to a coherent polariton state in bulk GaN microcavities in the strong-coupling regime. Nonresonant pulsed optical pumping produces rapid thermalization and yields a clear emission threshold of 1 mW, corresponding to an absorbed energy density of 29 microJ cm-2, 1 order of magnitude smaller than the best optically pumped (In,Ga)N quantum-well surface-emitting lasers (VCSELs). Angular and spectrally resolved luminescence show that the polariton emission is beamed in the normal direction with an angular width of +/-5 degrees and spatial size around 5 microm.

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Most cited references 24

Record: found
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Article: not found

Angle-Resonant Stimulated Polariton Amplifier

P. Savvidis, J. Baumberg, R. Stevenson … (2000)

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Record: found
Abstract: not found
Article: not found

Nonequilibrium condensates and lasers without inversion: Exciton-polariton lasers

A. Imamog¯lu, R. Ram, S Pau … (1996)

0 comments Cited 170 times – based on 0 reviews      Review now

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Record: found
Abstract: found
Article: not found

Polariton lasing vs. photon lasing in a semiconductor microcavity.

Hui Hong Deng, Gregor Weihs, David W. Snoke … (2003)

Nearly one decade after the first observation of Bose-Einstein condensation in atom vapors and realization of matter-wave (atom) lasers, similar concepts have been demonstrated recently for polaritons: half-matter, half-light quasiparticles in semiconductor microcavities. The half-light nature of polaritons makes polariton lasers promising as a new source of coherent and nonclassical light with extremely low threshold energy. The half-matter nature makes polariton lasers a unique test bed for many-body theories and cavity quantum electrodynamics. In this article, we present a series of experimental studies of a polariton laser, exploring its properties as a relatively dense degenerate Bose gas and comparing it to a photon laser achieved in the same structure. The polaritons have an effective mass that is twice the cavity photon effective mass, yet seven orders of magnitude less than the hydrogen atom mass; hence, they can potentially condense at temperatures seven orders of magnitude higher than those required for atom Bose-Einstein condensations. Accompanying the phase transition, a polariton laser emits coherent light but at a threshold carrier density two orders of magnitude lower than that needed for a normal photon laser in a same structure. It also is shown that, beyond threshold, the polariton population splits to a thermal equilibrium Bose-Einstein distribution at in-plane wave number k parallel > 0 and a nonequilibrium condensate at k parallel approximately 0, with a chemical potential approaching to zero. The spatial distributions and polarization characteristics of polaritons also are discussed as unique signatures of a polariton laser.