Bose-Einstein condensation of excitons and polaritons

Light effective mass ideal
for Bose quantum effects:
(Imamoglu 1996?) !
||
!
LP effective mass ~ 10 -4 m e
r s ~ " dB
n "1/ d ~ h / mk BT
T ~ h 2 2 / d
n
m
Why not use bare cavity photons?
paid for by reduced lifetime ~ 10 ps
!
...photons are (nearly) non-interacting.
Excitons have strong short-range interaction
polariton = “photon dressed with mass and hard core repulsion”