Quantum Fluctuations in Electrical Circuits

D. Vion, A. Aassime, Audrey Cottet +5 more

WU Hai-bo

For different states of the mesoscopic capacitive coupled electric circuit, reduction of quantum fluctuations induced by the coupling was studied. If the coupled circuit is at its ground state, or initially the system is decoupled, quantum fluctuations of the electric charge everywhere can be reduced, but that of the electric current can not. If initially the coupling part is open, quantum fluctuations of the current in the component circuits can not be squeezed; but quantum fluctuations of the current in the coupling part and quantum fluctuations of the charge everywhere can be reduced.

Bing Yuan

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.

E. S. R. Gopal

Mai-Lin Liang, Yuan Bing, 天津大学理学院应用物理系，天津 300072

Using a new quantization idea of the damped electric circuit, the inductive-coupled electric circuit is quantized when there exist resistances in the component circuits. Quantum fluctuations are calculated and the temperature effects included.

Jesse Van Griensven Thé, Roydon Andrew Fraser, José R. Rosas-Bustos