https://doi.org/10.1140/epjd/e2011-20194-0
Regular Article
Emission spectra and intrinsic optical bistability in a two-level medium
1 Institute for Spectroscopy of the Russian Academy of Sciences, Fisicheskaya Str. 5, 142190 Troitsk, Moscow region, Russia
2 State research center of Russian Federation Troitsk Institute for Innovation and Fusion Research, Pushkovykh Str., vlad. 12, 142190 Troitsk, Moscow region, Russia
3 Vladimir State University, Gorkogo Str. 87, 600000 Vladimir, Russia
a e-mail: dkuznet@yandex.ru
Received: 31 March 2011
Received in final form: 15 July 2011
Published online: 6 October 2011
Scattering of resonant radiation in a dense two-level medium is studied theoretically accounting for local field effects and renormalisation of the resonance frequency. Intrinsic optical bistability is viewed as switching between different spectral patterns of fluorescent light controlled by the incident field strength. Response spectra are calculated analytically for the entire hysteresis loop of atomic excitation. The equations to describe the non-linear interaction of an atomic ensemble with light are derived from the Bogolubov-Born-Green-Kirkwood-Yvon hierarchy for reduced single particle density matrices of atoms and quantised field modes and their correlation operators. The spectral power of scattered light with separated coherent and incoherent constituents is obtained straightforwardly within the hierarchy. The formula obtained for emission spectra can be used to distinguish between possible mechanisms suggested to produce intrinsic bistability in experiments.
© EDP Sciences, Società Italiana di Fisica and Springer-Verlag 2011
