Kondo effect in gapless superconductors

Lech S. Borkowski; P. J. Hirschfeld

doi:10.1103/PhysRevB.46.9274

← Back to search

Kondo effect in gapless superconductors

Lech S. Borkowski, P. J. Hirschfeld

DOI 10.1103/PhysRevB.46.9274 · Physical Review B

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 present a self-consistent theory of Kondo impurities in gapless unconventional superconductors valid in the Fermi-liquid regime T≲TK. The impurity degrees of freedom are treated using the large-N slave-boson technique, leading to tractable equations describing the interplay between the Kondo effect and superconductivity. We show that for a single impurity in a superconductor with density of states N(ω)∼‖ω‖r, there exists a critical coupling Jc below which the Kondo effect does not occur. However, for r≤1 or N=2 any finite concentration of impurities drives Jc→0. The theory provides microscopic support for phenomenological models of resonant impurity scattering in heavy-fermion systems.

Source-reported materials — not catalogue approval

Formula	Reported Tc (K)	Pressure (GPa)	Type
UPt3 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
UBe13 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
URu2Si2 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
CeCu2Si2 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown