Charge fluctuations in a quantum point contact attached to a superconducting lead

Article

关键词: 2-DIMENSIONAL ELECTRON-SYSTEM;    MAGNETIC-FIELD;    SHOT-NOISE;    TRANSPORT;   

DOI  :  10.1103/PhysRevB.60.R12581

来源: SCIE

【 摘 要 】

We show how to calculate the charge noise spectrum in a normal mesoscopic conductor, which is capacitively coupled to a macroscopic gate, when this conductor is attached to L normal leads and M superconducting leads, the only restriction being that the superconducting leads must be at the same chemical potential. We then proceed to examine results for a quantum point contact (QPC) in a normal lead connecting to a superconductor. Of interest is the fluctuating current in a gate capacitively coupled to a QPC. The results are compared with the case when all leads are normal. We find a doubling of the equilibrium charge fluctuations and a large enhancement (> 2) in the current noise spectrum to first order in \eV\, when a channel in the QPC is opening. [S0163-1829(99)50342-1].

【 授权许可】

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