Stationary light pulses in cold atomic media and without Bragg gratings.
We study the creation of stationary light pulses (SLPs), i.e., light pulses without motion, based on the effect of electromagnetically induced transparency with two counterpropagating coupling fields in cold atoms. We show that the Raman excitations created by counterpropagating probe and coupling fields prohibit the formation of SLPs in media of cold and stationary atoms such as laser-cooled atom clouds, Bose condensates or color-center crystals. A method is experimentally demonstrated to suppress these Raman excitations and SLPs are realized in laser-cooled atoms. Furthermore, we report the first experimental observation of a bichromatic SLP at wavelengths for which no Bragg grating can be established. Our work advances the understanding of SLPs and opens a new avenue to SLP studies for few-photon nonlinear interactions.
Lin
Yen-Wei
YW
Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan, Republic of China.
Liao
Wen-Te
WT
Peters
Thorsten
T
Chou
Hung-Chih
HC
Wang
Jian-Siung
JS
Cho
Hung-Wen
HW
Kuan
Pei-Chen
PC
Yu
Ite A
IA