电磁诱导透明窗口中温度、功率及偏振特性对四波混频信号的影响

Exploration of Temperature,Power and Polarization Dependence of Four-Wave Mixing in EIT Window

电磁诱导透明(EIT)效应改变了介质的吸收特性,导致了线性极化率的抑制和非线性极化率的提高,从而可以实现高效率四波混频的产生。实现了基于EIT的高效四波混频,且研究了样品温度、入射光功率和入射光偏振状态对四波混频信号的影响特性。研究发现,温度对样品铷的两个同位素87Rb和85Rb的影响有所差别,它们分别存在一个最佳工作温度使得四波混频信号最大;四波混频信号强度正比于入射光的功率;通过偏振调制四波混频可实现对四波混频的抑制和增强控制。

Absorption characteristics of a medium can be changed by electromagnetically induced transparency（EIT）.Linear susceptibility is suppressed and nonlinear susceptibility is enhanced,thereby four-wave mixing of higher conversion efficiency can be generated.Four-wave mixing of higher conversion efficiency in EIT window is successfully measured,and the dependence of the four-wave mixing signal on the temperature of the sample,the power and the polarization state of the input beam are discussed respectively.The result shows that 1） ^87Rb and ^85Rb are affected differently by temperature and a best temperature exists for them respectively to make the signal greatest,2） four-wave mixing signal is proportional to the power of the input beam,and 3） the polarization could be used to restrain or strengthen the four-wave mixing signal.