Ha'erbin gongye daxue xuebao
Quantum fluctuations in capacitive coupled electric circuits at finite temperature
Bing Yuan
Abstract
Using the thermal field dynamics, the quantum fluctuations in the capacitive coupled electric circuits at finite temperature are calculated. At zero temperature, the eigenstates of the capacitive coupled electric circuit are the displaced Fock states. At finite temperature, the states become the thermal displaced Foek states. The results show that, in the coupling part of the circuit, which is not studied in former discussions, capacitance coupling reduces the quantum fluctuation of the electric charge and increase that of the electric current.