title: Probing superconducting phase fluctuations from the current noise spectrum of pseudogapped metal-superconductor tunnel junctions.
abstract: We study the current noise spectra of a tunnel junction of a metal with strong pairing phase fluctuation and a superconductor. It is shown that there is a characteristic peak in the noise spectrum at the intrinsic Josephson frequency omega(J) = 2eV when omega(J) is smaller than the pairing gap but larger than the pairing scattering rate. In the presence of an ac voltage, the tunneling current noise shows a series of characteristic peaks with increasing dc voltage. Experimental observation of these peaks will give direct evidence of the pair fluctuation in the normal state of high- T(c) superconductors and the pair decay rate can be estimated from the half width of the peaks.
authors.affiliation: Physics Department, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
authors.forename: X
authors.initials: X
authors.lastname: Dai
authors.forename: T
authors.initials: T
authors.lastname: Xiang
authors.forename: T K
authors.initials: TK
authors.lastname: Ng
authors.forename: Z
authors.initials: Z
authors.lastname: Su