arXiv:1207.2299 · Europhysics Letters (EPL)
Identifying the orbital angular momentum of light based on atomic ensembles
Liang Han, Mingtao Cao, Ruifeng Liu, Hao Liu, Wenge Guo, Dong Wei, Shaoyan Gao, Pei Zhang, Hong Gao, Fuli Li
Abstract
We propose a scheme to distinguish the orbital angular momentum state of the Laguerre-Gaussian (LG) beam based on the electromagnetically induced transparency modulated by a microwave field in atomic ensembles. We show that the transverse phase variation of a probe beam with the LG mode can be mapped into the spatial intensity distribution due to the change of atomic coherence caused by the microwave. The proposal may provide a useful tool for studying higher-dimensional quantum information based on atomic ensembles.