脉冲激发三能级体系半导体量子点的单光子发射效率  

Efficiency of single photon emission in three-level system of semiconductor quantum dots with pulsed excitation

作　　者：李耀义[1] 程木田[1] 周慧君[1] 刘绍鼎[1] 王取泉[1] 薛其坤[2] 

机构地区：[1]武汉大学物理系,武汉430072 [2]中国科学院物理研究所表面物理国家重点实验室,北京100080

出　　处：《物理学报》2006年第4期1781-1786,共6页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:10534030;10474075)资助的课题.

摘　　要：研究了脉冲激发下单个半导体量子点中单光子发射的统计特性.在旋转波近似条件下,由系统粒子数演化主方程并结合量子回归理论推导了二阶相关函数的运动方程,利用此方程讨论了二阶相关函数随输入脉冲面积的关系.在窄脉冲宽度的脉冲激发下,单光子的发射概率p和效率η都随着强度的增强而产生振荡.研究表明,采用窄脉冲宽度,当输入脉冲面积在π附近时可以得到较高的单光子发射效率.The statistic characteristics of single photon emission in single semiconductor quantum dot with pulse excitation have been investigated. With rotating-wave approximation, we deduce the dynamics equations including second-order correlation function from the master equations of the populations and discuss the correlation function of photon emission from the exciton combination under different input pulse areas. There will appear an apparant split peak around zero time delay under strong excitation. For short pulse width, the probability of single photon emission p and the efficiency of single photon emission η oscillate as the excitation intensity increases. It is revealed that high efficient single photon emissions can be realized in this system when excited with input pulse area about π and short pulse width.

关 键 词：半导体量子点 单光子发射 三能级系统 发射效率 

分 类 号：O471.1[理学—半导体物理]