Sensitivity of a cavityless optomechanical system

Abstract

We study the possibility of revealing a weak coherent force by using a pendular mirror as a probe, and coupling this to a radiation field, which acts as the meter, in a cavityless configuration. We determine the sensitivity of such a scheme and show that the use of an entangled meter state greatly improves the ultimate detection limit. We also compare this scheme with that involving an optical cavity.Comment: 4 pages, RevTex file, 2 eps figures, provisionally accepted by Phys. Rev.