Quantum state singlet-triplet character control in lithium-7

Ömer Salihoglu, Peng Qi, Sonja Ingram +2 more

J. R. Petta

Ergin H. Ahmed, Xinhua Pan, John Huennekens +1 more

In this work we demonstrate optical control of the singlet-triplet probability distribution in the outcome of a collisional process involving lithium dimers and argon atoms. The control is achieved using the Autler-Townes effect to manipulate the spin character of a spin-orbit coupled pair of levels serving as a ``gateway'' between the singlet and triplet electronic state manifolds.

Rong Zhang, Shanti Deemyad

A. M. Lyyra, F. C. Spano, Jun Qi +1 more

We have demonstrated Autler-Townes splitting in molecular lithium using continuous wave triple resonance spectroscopy. The Autler-Townes split double resonance lineshape consists of a superposition of several narrower twin peaks, one for each | M j |. The splitting is proportional to | M j | enabling separation of the individual Mj peaks. Thus, excitation of an individual magnetic sublevel can be used to align the angular momentum of nonpolar molecules all-optically. We also propose a novel quantum control scheme based on using a coupling laser to create dressed states of controllable molecular character. Preliminary calculations are presented for variable singlet triplet character.

Ergin H. Ahmed, Sonia Ingram, Teodora Kirova +5 more

We have demonstrated quantum control of the spin-orbit interaction based on the Autler-Townes (ac-Stark) effect in a molecular system using a cw optical field. We show that the enhancement of the spin-orbit interaction between a pair of weakly interacting singlet-triplet rovibrational levels, G (1)Π(g)(v=12,J=21,f)-1 (3)Σ(g)(-)(v=1,N=21,f), separated by 750 MHz in the lithium dimer, depends on the Rabi frequency (laser power) of the control laser. The increase in the spin-orbit interaction due to the control field is observed as a change in the spin character of the individual components of the perturbed pair.