Optical signatures of quantum phase transitions in a light-matter systemT. C. Jarrett, A. Olaya-Castro and N. F. Johnson
Centre for Quantum Computation and Department of Physics, Clarendon Laboratory, University of Oxford Oxford, OX1 3PU, UK
received 19 October 2006; accepted in final form 29 November 2006; published February 2007
published online 5 February 2007
Information about quantum phase transitions in conventional condensed matter systems, must be sought by probing the matter system itself. By contrast, we show that mixed matter-light systems offer a distinct advantage in that the photon field carries clear signatures of the associated quantum critical phenomena. Having derived an accurate, size-consistent Hamiltonian for the photonic field in the well-known Dicke model, we predict striking behavior of the optical squeezing and photon statistics near the phase transition. The corresponding dynamics resemble those of a degenerate parametric amplifier. Possible realizations include atom-cavity, nanostructure-cavity, and nanostructure-photonic-band-gap systems.
42.50.Fx - Cooperative phenomena in quantum optical systems .
73.43.Nq - Quantum phase transitions.
32.80.-t - Photon interactions with atoms.
© Europhysics Letters Association 2007