Room-temperature polariton lasing in semiconductor microcavities.
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.
Christopoulos
S
S
School of Physics and Astronomy, University of Southampton, Highfield, Southampton, SO17 1BJ, UK.
von Högersthal
G Baldassarri Höger
GB
Grundy
A J D
AJ
Lagoudakis
P G
PG
Kavokin
A V
AV
Baumberg
J J
JJ
Christmann
G
G
Butté
R
R
Feltin
E
E
Carlin
J-F
JF
Grandjean
N
N