本文将三网孔介观电容耦合电路系统看作一个正则系综,通过计算正则系综的密度矩阵方程得出有限温度下耦合电路中电荷和磁通量的量子涨落.高频下,电路中电荷的量子涨落类似于低温下的情形,表现为典型的量子噪音;磁通量的量子涨落则不单是零点的量子涨落,总是和温度有关;绝对零度下,输入、输出网孔中电荷和磁通量不确定度的乘积保持相等.

The mesoscopic capacitor coupled circuit of 3 meshes can be considered as the canon- ical ensemble. It gets at quantum fluctuations of both charge and magnetic flux in the coupled circuit at a finite temperature by calculating the density matrix of the canonical ensemble. Our results show that quantum fluctuations of both charge and magnetic flux depend on the tem- perature. With high frequency, charge fluctuation, which are similar to the situation of low temperature, show typical quantum noise, and it is impertinent to temperature. But magnetic flux fluctuation not only is quantum fluctuation of zero point temperature, also is always con- nected with temperature. At absolute zero point temperature, the uncertainty relation of both charge and magnetic flux in the input mesh or in the output mesh is constant.