Tunneling Anomaly in a Superconductor above the Paramagnetic Limit

I. L. Aleiner; B. L. Altshuler

doi:10.1103/PhysRevLett.79.4242

← Back to search

Tunneling Anomaly in a Superconductor above the Paramagnetic Limit

I. L. Aleiner, B. L. Altshuler

DOI 10.1103/PhysRevLett.79.4242 · 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 study the tunneling density of states (DOS) in superconducting systems driven by Zeeman splitting EZ into the paramagnetic phase. We show that, even though the BCS gap disappears, superconducting fluctuations cause a strong DOS singularity in the vicinity of energies −E* for electrons polarized along the magnetic field and E* for the opposite polarization. The position of the singularity E*=12(EZ+EZ2−Δ2) (where Δ is the BCS gap at EZ=0) is universal. We find analytically the shape of the DOS for different dimensionalities of the system. For ultrasmall grains the singularity has the form of the hard gap, while in higher dimensions it appears as a significant though finite dip.

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