电磁诱导吸收介质中探针场的量子噪声特性

Quantum Noise Property of Probe Light in EIA Medium

在N型原子系统中,在二束强的耦合场作用于介质对探针场体现出很强的诱导吸收作用,与此同时,强吸收引起的自发辐射噪声会影响探针场的量子噪声特性。该文章研究了输入的量子化探测场在经过电磁诱导吸收介质后的噪声特性变化,数值模拟得出,通过调节控制场的强度可以使得探测场的噪声谱图形在吸收窗口范围内产生震荡分裂,噪声最小值处于一定的探针场失谐处。

In the case of N-type atomic ensemble, which is affectal by two strong beams, the electromagntically induce absorption is obsewed, Simultaneously with the influence of spontaneous emission which is a result of strong absorption, the quantum noise spectrum will be changed. In this paper, the output noise spectrum of the amplitude quadrature in the special quantum probe field, which has passed through the N-type electromagnetically induced transparent medium, is analyzed theoretically. After numerical simulation we find that by means of modulating the light intensity, a small splitting could appear in the noise spectrum of the corresponding probe light, similar to that in the absorbtion peak, but yet the minimum of the noise can only appear at that very detuned frequency where exists the minimum of absorption intensity.