Graciana Puentes, Giorgio Colangelo, Robert J. Sewell, Morgan W. Mitchell
Planar quantum squeezed states, i.e. quantum states which are squeezed in two orthogonal components on a plane, have recently attracted attention due to their applications in atomic interferometry and quantum information [1,2]. Unlike the quadratures of the radiation field which are inherently transverse, simultaneous squeezing in two orthogonal spin components can be achieved due to the fact that angular momentum belongs to SU(2,3) group, a feature which can be exploited to tailor the corresponding commutator between two such operators, and reduce orthogonal variances simultaneously. In this paper, we present a novel scheme for planar quantum squeezing via quantum non-demolition (QND) measurements in spin-1 systems [3]. The QND measurement is achieved via paramagnetic Faraday rotation on off-resonant probe light, and the planar quantum squeezing is obtained with the aid of an external magnetic field which introduces a Larmor precession on the plane where squeezing takes place. We show that planar quantum squeezed states can be used to reconstruct an arbitrary quantum parameter, such as a phase, without any prior information, and could therefore find relevant applications in single-shot atomic magnetometry where temporal fluctuation can prevent the implementation of iterative procedures.
View original:
http://arxiv.org/abs/1211.4862
No comments:
Post a Comment