Topical Meeting on Optical Bistability (OB)
Optical Bistability Experiments Using Samarium Vapour
Weston J. Sandle, Christian G. Parigger
Abstract
Experimental investigations of optical bistability (OB) for systems with degenerate lower states have up to now relied principally on atomic sodium [1-4]. The study of the influence of lower level coherence effects in OB [5] is greatly aided by the use of a nonlinear medium having a transition with integral electronic angular momentum character. A suitable choice upon which we report here is the 4f6 6s2 (7F1) to 4f6 6s6p (7Foo) 570.68-nm transition in SmI, driven by linearly polarized laser excitation in a near-concentric Fabry-Perot cavity. Unlike the case of the Na J = 1/2 to J = 1/2 D1 transition, for which polarization asymmetry in switching (PS) develops spontaneously [1-4], for the above transition we find that the symmetry in the polarization is conserved. No polarization differences of σ+ with respect to σ− develop in the output from the optical cavity. This behaviour accords with the theoretical expectation [6] that PS is suppressed by transverse optical pumping.