Universität zu Köln

Gelhausen, Jan ORCID: 0000-0003-0705-8566 and Buchhold, Michael ORCID: 0000-0001-5194-9388 (2018). Dissipative Dicke model with collective atomic decay: Bistability, noise-driven activation, and the nonthermal first-order superradiance transition. Phys. Rev. A, 97 (2). COLLEGE PK: AMER PHYSICAL SOC. ISSN 2469-9934

Full text not available from this repository.

Abstract

The Dicke model describes the coherent interaction of a laser-driven ensemble of two-level atoms with a quantized light field. It is realized within cavity QED experiments, which in addition to the coherent Dicke dynamics feature dissipation due to, e.g., atomic spontaneous emission and cavity photon loss. Spontaneous emission supports the uncorrelated decay of individual atomic excitations as well as the enhanced collective decay of an excitation that is shared by N atoms and whose strength is determined by the cavity geometry. We derive a many-body master equation for the dissipative Dicke model including both spontaneous emission channels and analyze its dynamics on the basis of Heisenberg-Langevin and stochastic Bloch equations. We find that the collective loss channel leads to a region of bistability between the empty and the superradiant state. Transitions between these states are driven by nonthermal Markovian noise. The interplay between dissipative and coherent elements leads to a genuine nonequilibrium dynamics in the bistable regime, which is expressed via a nonconservative force and a multiplicative noise kernel appearing in the stochastic Bloch equations. We present a semiclassical approach, based on stochastic nonlinear optical Bloch equations, which for the infinite-range Dicke model become exact in the large-N-limit. The absence of an effective free-energy functional, however, necessitates the inclusion of fluctuation corrections with O(1/N) for finite N < infinity to locate the nonthermal first-order phase transition between the superradiant and the empty cavity.

Item Type:	Journal Article
Creators:	Creators Email ORCID ORCID Put Code Gelhausen, Jan UNSPECIFIED orcid.org/0000-0003-0705-8566 UNSPECIFIED Buchhold, Michael UNSPECIFIED orcid.org/0000-0001-5194-9388 UNSPECIFIED
URN:	urn:nbn:de:hbz:38-196183
DOI:	10.1103/PhysRevA.97.023807
Journal or Publication Title:	Phys. Rev. A
Volume:	97
Number:	2
Date:	2018
Publisher:	AMER PHYSICAL SOC
Place of Publication:	COLLEGE PK
ISSN:	2469-9934
Language:	English
Faculty:	Faculty of Mathematics and Natural Sciences
Divisions:	Faculty of Mathematics and Natural Sciences > Department of Physics > Institute for Theoretical Physics
Subjects:	no entry
Uncontrolled Keywords:	Keywords Language OPTICAL BISTABILITY; DYNAMICS; GAS; RENORMALIZATION; SYSTEMS Multiple languages Optics; Physics, Atomic, Molecular & Chemical Multiple languages
Refereed:	Yes
URI:	http://kups.ub.uni-koeln.de/id/eprint/19618