Ultranarrow Optical Resonances

Duncan G. Steel, Stephen Colby Rand, J. Remilard

S. Mathur, U. N. Upadhyaya

Shintaro Taie, Shunsuke Watanabe, Tomohiro Ichinose +1 more

We reveal the existence of high-density Feshbach resonances in the collision between the ground and metastable states of ^{171}Yb and coherently produce the associated Feshbach molecules by photoassociation. The extremely small transition rate is overcome by the enhanced Franck-Condon factor of the weakly bound Feshbach molecule, allowing us to observe Rabi oscillations with long decay time between an atom pair and a molecule in an optical lattice. We also perform the precision measurement of the binding energies, which characterizes the observed resonances. The ultranarrow photoassociation will be a basis for practical implementation of optical Feshbach resonances.

Vladilen S Letokhov, Veniamin P. Chebotayev

Yandong Peng, Luling Jin, Yueping Niu +1 more

A scheme for obtaining a tunable ultranarrow linewidth of a cavity due to an embedded four-level atomic medium with double-dark resonances is proposed. It is shown that the steep dispersion induced by double-dark resonances in the transparency window leads to the ultranarrow transmission peak. Compared with the case of a single-dark resonance system, the linewidth can be narrowed even by one order under proper conditions. Furthermore, the position of the ultranarrow peak can be engineered by varying the detuning of the control field.

R. M. Whitley