Effect of Level Statistics on Superconductivity in Ultrasmall Metallic Grains

Robert A. Smith; Vinay Ambegaokar

doi:10.1103/PhysRevLett.77.4962

← Back to search

Effect of Level Statistics on Superconductivity in Ultrasmall Metallic Grains

Robert A. Smith, Vinay Ambegaokar

DOI 10.1103/PhysRevLett.77.4962 · Physical Review Letters

T1

Active bibliographic source — not scientific approval

Bibliographic access preserves source history; it does not approve extracted materials or validate reported claims. Review warnings on each occurrence separately.

Abstract

We examine the destruction of superconducting pairing in metallic grains as their size is decreased for both even and odd numbers of electrons. This occurs when the average level spacing d is of the same order as the BCS order parameter Δ. The energy levels of these grains are randomly distributed according to random matrix theory, and we must work statistically. We find that the average value of the critical level spacing is larger than that for the model of equally spaced levels for both parities, and derive numerically the probability densities Po,e(d) that a grain of mean level spacing d shows pairing.

Source-reported materials — not catalogue approval

Formula	Reported Tc (K)	Pressure (GPa)	Type
Al Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown