论文标题
非平衡双量子点的动力充电易感性
Dynamical charge susceptibility in nonequilibrium double quantum dots
论文作者
论文摘要
双量子点是实现Qubits的有前途的两国量子系统之一。为了成功地操纵和阅读量子系统中的信息，控制系统对栅极电压的电荷响应是由动态电荷敏感性所填充的。从理论上讲，我们通过使用功能积分方法并得出其一般的分析表达来研究非平衡双量子点的该量。一个人突出显示了两行最大线作为点级能的函数，它们在偏置电压的作用下分裂。在低频限制中，我们得出了等效量子RC电路的电容和电荷松弛电阻，其$ r $变化范围的差异显着，具体取决于系统是否串联连接还是并行连接。通过合并一个额外的三胞胎状态以描述带有自旋的双重量子点的情况，我们获得了与自旋量子置量系统中最新的实验观察的定性一致的谐振相位响应的结果。这些结果表明，通过对双量子点的动态电荷敏感性的知识带来的大量信息，并具有潜在的旋转Qubits应用。
Double quantum dots are one of the promising two-state quantum systems for realizing qubits. In the quest of successfully manipulating and reading information in qubit systems, it is of prime interest to control the charge response of the system to a gate voltage, as filled in by the dynamical charge susceptibility. We theoretically study this quantity for a nonequilibrium double quantum dot by using the functional integral approach and derive its general analytical expression. One highlights the existence of two lines of maxima as a function of the dot level energies, each of them being split under the action of a bias voltage. In the low frequency limit, we derive the capacitance and the charge relaxation resistance of the equivalent quantum RC-circuit with a notable difference in the range of variation for $R$ depending on whether the system is connected in series or in parallel. By incorporating an additional triplet state in order to describe the situation of a double quantum dot with spin, we obtain results for the resonator phase response which are in qualitative agreement with recent experimental observations in spin qubit systems. These results show the wealth of information brought by the knowledge of dynamical charge susceptibility in double quantum dots with potential applications for spin qubits.
