Effects of impurity vertex correction on the NMR coherence peak in {ital s}-wave superconductors

Journal Article · Fri Sep 01 04:00:00 EDT 1995 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.52.7549· OSTI ID:115864

Choi, H ^[1]; Mele, E J ^[2]

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1. Department of Physics, Sung Kyun Kwan University, Suwon 440-746 (Korea, Republic of)
2. Department of Physics, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States)

We study the effects of nonmagnetic impurity vertex correction on nuclear spin-lattice relaxation rate 1/{ital T}{sub 1} of conventional {ital s}-wave superconductors within the Eliashberg formalism. We obtain, with a self-consistent {ital t}-matrix treatment of impurity scatterings, the expression for impurity vertex function and nuclear spin-lattice relaxation rate. The 1/{ital T}{sub 1} is evaluated with a simple approximation on angular average, and found to agree in clean limit with the previous result that 1/({ital T}{sub 1}{ital T}) remains unrenormalized under the impurity vertex correction. As dirtiness is increased, on the other hand, the coherence peak in 1/({ital T}{sub 1}{ital T}) is found to increase due to the impurity vertex correction. This result is discussed in connection with the experimental observations on conventional superconductors.

• OSTI ID: 115864
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 10 Vol. 52; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
CRYSTAL DEFECTS
GORKOV-ELIASHBERG THEORY
NMR SPECTRA
RELAXATION TIME
S WAVES
SELF-CONSISTENT FIELD
SPIN-LATTICE RELAXATION
SUPERCONDUCTORS
TRANSFER MATRIX METHOD