Abstract

We suggest a technique based on the transfer of topological charge from applied laser radiation to directional and coherent optical fields generated in ladder-type excited atomic media to identify the major processes responsible for their appearance. As an illustration, in Rb vapors, we analyze transverse intensity and phase profiles of the forward-directed collimated blue and near-IR light using self-interference and astigmatic transformation techniques when either or both of two resonant laser beams carry orbital angular momentum. Our observations unambiguously demonstrate that emission at 1.37 μm is the result of a parametric four-wave mixing process involving only one of the two applied laser fields.

© 2015 Optical Society of America

Arithmetic with optical topological charges in stepwise-excited Rb vapor

Alexander M. Akulshin, Irina Novikova, Eugeniy E. Mikhailov, Sergey A. Suslov, and Russell J. McLean
Opt. Lett. 41(6) 1146-1149 (2016)

Nonlinear optical memory for manipulation of orbital angular momentum of light

R. A. de Oliveira, G. C. Borba, W. S. Martins, S. Barreiro, D. Felinto, and J. W. R. Tabosa
Opt. Lett. 40(21) 4939-4942 (2015)

Optical angular momentum manipulations in a four-wave mixing process

Nikunj Prajapati, Nathan Super, Nicholas R. Lanning, Jonathan P. Dowling, and Irina Novikova
Opt. Lett. 44(4) 739-742 (2019)

Storage of orbital angular momenta of light via coherent population oscillation

A. J. F. de Almeida, S. Barreiro, W. S. Martins, R. A. de Oliveira, D. Felinto, L. Pruvost, and J. W. R. Tabosa
Opt. Lett. 40(11) 2545-2548 (2015)

Orbital angular momentum generation via a spiral phase microsphere

Yan Zhou, Hui Gao, Jinghua Teng, Xiangang Luo, and Minghui Hong
Opt. Lett. 43(1) 34-37 (2018)