双量子点电荷比特的散粒噪声谱  

Shot noise spectrum of a double quantum dot charge qubit

作　　者：施振刚 文伟[1,2] 谌雄文[1,2] 向少华[1,2] 宋克慧[1,2] 

机构地区：[1]怀化学院物理与信息工程系,怀化418008 [2]怀化学院信息科学研究所,怀化418008

出　　处：《物理学报》2010年第5期2971-2975,共5页Acta Physica Sinica

基　　金：湖南省教育厅科研基金重点项目(批准号:06A055;09B079);怀化学院青年基金(批准号:HHUQ2009-07;HHUQ2009-09)资助的课题~~

摘　　要：考虑基底声子热库的耗散效应,推导了双量子点电荷比特的主方程,并利用全计数统计方法计算了双量子点电荷比特的平均电流和Fano因子.结果表明:声子热库的耗散引起平均电流关于其峰值的非对称分布和Fano因子双峰的非对称分布,并且随着声子热库温度T的升高,平均电流的非对称分布越强,Fano因子的峰值逐渐降低,直至超泊松分布行为消失.We derive the master equation of a double quantum dot charge qubit by taking into account the dissipative effects of the phonon -bath environment,and study the current noise spectrum of the double quantum dot charge qubit in terms of full counting statistics. It is found that the current is asymmetric about the current peak. The Fano factor displays an asymmetric double-peak structure,the asymmetry is due to the dissipations induced by the phonon bath. With increasing temperature T of the phonon bath,the current resonance broadens,the Fano factor peaks become smaller,and the super-Poissonian behavior vanishes.

关 键 词：双量子点电荷比特 主方程 全计数统计 散粒噪声 

分 类 号：O431.2[机械工程—光学工程]