Eur. Phys. J. D 62, 245-253 (2011)
https://doi.org/10.1140/epjd/e2010-09661-x

Entangled entanglement in Raman lasers

Department of Physics, Huazhong Normal University, Wuhan 430079, P.R. China

^a e-mail: xmhu@phy.ccnu.edu.cn

Received: 29 December 2009
Received in final form: 24 June 2010
Published online: 4 February 2011

Abstract

We show that entangled entanglement can be obtained from a multimode Raman laser. In this system, all lasing modes constitute a quantum-beat. Equivalently, one collective mode is operated well above threshold and exhibits the sub-Poissonian statistics, while other orthonormal collective modes are excluded from the interacting system and stay in vacuum states. This determines entanglement between any two sub-collections, in each of which exists entanglement between any two sub-sub-collections, and so on, if present. This scheme is accessible based on the recent experimental progress in Raman lasers.