From polariton condensates to highly photonic quantum degenerate states of bosonic matter.
Bose-Einstein condensation (BEC) is a thermodynamic phase transition of an interacting Bose gas. Its key signatures are remarkable quantum effects like superfluidity and a phonon-like Bogoliubov excitation spectrum, which have been verified for atomic BECs. In the solid state, BEC of exciton-polaritons has been reported. Polaritons are strongly coupled light-matter quasiparticles in semiconductor microcavities and composite bosons. However, they are subject to dephasing and decay and need external pumping to reach a steady state. Accordingly the polariton BEC is a nonequilibrium process of a degenerate polariton gas in self-equilibrium, but out of equilibrium with the baths it is coupled to and therefore deviates from the thermodynamic phase transition seen in atomic BECs. Here we show that key signatures of BEC can even be observed without fulfilling the self-equilibrium condition in a highly photonic quantum degenerate nonequilibrium system.
Experimentelle Physik 2, Technische Universität Dortmund, 44221 Dortmund, Germany.
Marc
M
Assmann
Jean-Sebastian
JS
Tempel
Franziska
F
Veit
Manfred
M
Bayer
Arash
A
Rahimi-Iman
Andreas
A
Löffler
Sven
S
Höfling
Stephan
S
Reitzenstein
Lukas
L
Worschech
Alfred
A
Forchel
Phys Rev Lett. 2008 Aug 8;101(6):067404
18764503
Science. 2009 Jul 17;325(5938):297-300
19608912
Nature. 2009 Jul 9;460(7252):245-9
19587766
Nature. 2009 Jan 15;457(7227):291-5
19148095
Phys Rev Lett. 2005 May 13;94(18):187401
15904409
Phys Rev Lett. 2010 Oct 29;105(18):186402
21231119
Science. 2002 Oct 4;298(5591):199-202
12364801
Phys Rev Lett. 2008 Sep 26;101(13):136409
18851475
Phys Rev Lett. 2010 Jul 30;105(5):056401
20867938
Opt Express. 2010 Sep 13;18(19):20229-41
20940914
Phys Rev Lett. 2008 Feb 15;100(6):067402
18352514
Science. 2009 Nov 13;326(5955):974-6
19965506
Proc Natl Acad Sci U S A. 2003 Dec 23;100(26):15318-23
14673089
Nature. 2006 Sep 28;443(7110):409-14
17006506
Science. 2007 May 18;316(5827):1007-10
17510360
Phys Rev Lett. 2006 Jun 16;96(23):230602
16803361
Phys Rev Lett. 2008 Oct 3;101(14):146404
18851551
Phys Rev Lett. 2007 Oct 5;99(14):140402
17930649
Phys Rev Lett. 2006 Oct 6;97(14):146402
17155273