Journal of Xiamen University
Relation Between the Wehrl Entropy and the Quantum Effects of Mesoscopic Circuit
Xing-Lei Xu
Abstract
By using the quantum canonic ensemble theory,the density matrix and the Wehrl entropy of a harmonic oscillator are derived in a thermal field.The mesoscopic RLC series circuit is equivalent to a harmonic oscillator.The relation between the Wehrl entropy and the quantum effects of mesoscopic circuit is proposed at a finite temperature.It is shown that the Wehrl entropy of a harmonic oscillator not only depends on the eigenfrequency,but also relies on the temperature.The quantum fluctuations of charge,magnetic flux and the corresponding uncertainty relation increase monotonously with the Wehrl entropy,thereby increase monotonously with the temperature,and consistent with results of the thermal field dynamics(TFD).So the Wehrl entropy can be regarded as a measurement of the quantum effects of the mesoscopic circuit.