耦合场线宽和强度对双简并四能级系统的吸收和衍射效率的影响  

Influence of Coupling-Field Linewidth and Intensity on Absorption and Diffraction efficiency in a Doubly Degenerate Four-Level System

作　　者：刘云[1] 王朴[1] 彭双艳[1] 

机构地区：[1]毕节学院理学院,贵州毕节551700

出　　处：《量子光学学报》2014年第3期241-247,共7页Journal of Quantum Optics

基　　金：贵州省科学技术厅;毕节市科学技术局;毕节学院科技联合基金(黔科合J字LKB[2013]17号)

摘　　要：采用密度矩阵方程,分别在引入耦合场线宽和强度、探测场频率变化以及耦合场频率与探测场频率之比变化的条件下,数值计算了双简并四能级原子系统中介质对探测场的吸收(增益)和相位光栅衍射效率的影响。结果表明:耦合场线宽的增大削弱了简并四能级原子相干;不考虑耦合场线宽(R=0)时的增益和衍射效率比考虑耦合场线宽(R≠0)时的大,在耦合光频率与探测光频率之比为ΩcΩp≈400时衍射效率最大可达到35%。Using density matrix equation, influence of the absorption（gain） of the probing field and diffraction efficiency of phase grating in a doubly degenerate four-level atomic system was calculated, under introducing laser field linewidth and intensities, and the variance of the probing field frequency and the variance of the ratio of coupling and probing field intensities, respectively. The results indicated that the increases of coupling field linewidth abates the atomic coherence in four-level system. When without considering（R= 0） the coupling field linewidth, the gain and diffraction efficiency are larger than them when considering（R≠0） the coupling field linewidth. We found that the first-order diffraction efficiency ofphase grating can reach up to 35 %, when variance of the ratio of coupling and probing field intensities Ωc/Ωp≈400.

关 键 词：耦合场线宽 原子相干 电磁感应吸收 衍射效率 

分 类 号：O431[机械工程—光学工程]