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Title: Room-Temperature Polariton Lasing in Semiconductor Microcavities

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 {mu}J cm{sup -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 deg. and spatial size around 5 {mu}m.

Authors:
; ; ; ; ; ; ; ; ; ;  [1];  [2]
  1. School of Physics and Astronomy, University of Southampton, Highfield, Southampton, SO17 1BJ (United Kingdom)
  2. (EPFL), Institute of Quantum Electronics and Photonics, 1015 Lausanne (Switzerland)
Publication Date:
OSTI Identifier:
20951131
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 12; Other Information: DOI: 10.1103/PhysRevLett.98.126405; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ENERGY DENSITY; GALLIUM NITRIDES; INDIUM NITRIDES; LASERS; LUMINESCENCE; OPTICAL PUMPING; QUANTUM WELLS; SEMICONDUCTOR MATERIALS; STRONG-COUPLING MODEL; TEMPERATURE RANGE 0273-0400 K; THERMALIZATION

Citation Formats

Christopoulos, S., Baldassarri Hoeger von Hoegersthal, G., Grundy, A. J. D., Lagoudakis, P. G., Kavokin, A. V., Baumberg, J. J., Christmann, G., Butte, R., Feltin, E., Carlin, J.-F., Grandjean, N., and Ecole Polytechnique Federale de Lausanne. Room-Temperature Polariton Lasing in Semiconductor Microcavities. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.126405.
Christopoulos, S., Baldassarri Hoeger von Hoegersthal, G., Grundy, A. J. D., Lagoudakis, P. G., Kavokin, A. V., Baumberg, J. J., Christmann, G., Butte, R., Feltin, E., Carlin, J.-F., Grandjean, N., & Ecole Polytechnique Federale de Lausanne. Room-Temperature Polariton Lasing in Semiconductor Microcavities. United States. doi:10.1103/PHYSREVLETT.98.126405.
Christopoulos, S., Baldassarri Hoeger von Hoegersthal, G., Grundy, A. J. D., Lagoudakis, P. G., Kavokin, A. V., Baumberg, J. J., Christmann, G., Butte, R., Feltin, E., Carlin, J.-F., Grandjean, N., and Ecole Polytechnique Federale de Lausanne. Fri . "Room-Temperature Polariton Lasing in Semiconductor Microcavities". United States. doi:10.1103/PHYSREVLETT.98.126405.
@article{osti_20951131,
title = {Room-Temperature Polariton Lasing in Semiconductor Microcavities},
author = {Christopoulos, S. and Baldassarri Hoeger von Hoegersthal, G. and Grundy, A. J. D. and Lagoudakis, P. G. and Kavokin, A. V. and Baumberg, J. J. and Christmann, G. and Butte, R. and Feltin, E. and Carlin, J.-F. and Grandjean, N. and Ecole Polytechnique Federale de Lausanne},
abstractNote = {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 {mu}J cm{sup -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 deg. and spatial size around 5 {mu}m.},
doi = {10.1103/PHYSREVLETT.98.126405},
journal = {Physical Review Letters},
number = 12,
volume = 98,
place = {United States},
year = {Fri Mar 23 00:00:00 EDT 2007},
month = {Fri Mar 23 00:00:00 EDT 2007}
}
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