Cedraschi P, Ponomarenko VV, Buttiker M
Departement de Physique Theorique, Universite de Geneve, 24, quai Ernest Ansermet, CH-1211 Geneva 4, Switzerland.
Phys Rev Lett. 2000 Jan 10;84(2):346-9. doi: 10.1103/PhysRevLett.84.346.
The ground state of a phase-coherent mesoscopic system is sensitive to its environment. We investigate the persistent current of a ring with a quantum dot which is capacitively coupled to an external circuit with a dissipative impedance. At zero temperature, zero-point quantum fluctuations lead to a strong suppression of the persistent current with decreasing external impedance. We emphasize the role of displacement currents in the dynamical fluctuations of the persistent current and show that with decreasing external impedance the fluctuations exceed the average persistent current.
一个相位相干介观系统的基态对其环境很敏感。我们研究了一个带有量子点的环的持续电流，该量子点通过电容耦合到一个具有耗散阻抗的外部电路。在零温度下，零点量子涨落会导致随着外部阻抗减小，持续电流受到强烈抑制。我们强调位移电流在持续电流动态涨落中的作用，并表明随着外部阻抗减小，涨落超过了平均持续电流。
