Jack and Pearl Resnick
Institute for Advanced
Science and Technology
Ramat-Gan 52900
Israel

Nemi Gavra
Ph.D Student Phone: 03-5318429 Room: 64

Research

Studies of Atomic clocks based on Coherent opulation trapping(CPT) Recently we investigate a versatile vertical cavity surface-emitting laser (VCSEL) with a slight optical feedback from a simple wedge positioned at a well determined distance from the VCSEL. We use such a laser in conjunction with a miniature Rb atomic cell to detect the CPT when the external cavity mode spacing frequency corresponds to half the hyperfine frequency of Rb. Studies of stored light in a tripod system We experimentally demonstrate the double dark resonance windows characteristic of a four level tripod system such as the D2 line of 87Rb where the Fg = 1, mg = -1, 0,1 Zeeman sublevels form the bottom three levels and the Fe = 0 state is the upper level. Between the double dark resonance windows, a very narrow absorption resonance is observed whose line-width is shown to be sub-Doppler and subnatural. The sharp absorptive resonance is characterized as a function of applied magnetic field and pump laser power.

Publications

“Sub-Doppler and sub-natural narrowing of an absorption line” N. Gavra, M. Rosenbluh, T. Zigdon, A.D. Wilson-Gordon, H. Friedmann. Opt. Commun. 280 (2007) 374–378 "Enhancement in microwave modulation efficiency of vertical cavity surface-emitting laser by optical feedback”. N. Gavra, V. Ruseva, and M. Rosenbluh. Appl. Phys. Lett. 92, 221113 (2008)

Collaboration

Prof. Gadi Eisenstein from the Technion, www.ee.technion.ac.il/people/gad and Avinoam Stern, Accubeat LTD, www.accubeat.com on the subject of atomic clocks. Prof. Arlene Gordon, Prof. H. Friedmann, Tzurit Zigdon and Asaf Eilam from the Chemistry Department of Bar-Ilan University. www.ch.biu.ac.il/php/general/people.php