Premium
Van Hove Singularity in (s + id)‐Wave Cuprate Superconductors
Author(s) -
Teng H. Y.,
Liu M.,
Xing D. Y.
Publication year - 1997
Publication title -
physica status solidi (b)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.51
H-Index - 109
eISSN - 1521-3951
pISSN - 0370-1972
DOI - 10.1002/1521-3951(199705)201:1<203::aid-pssb203>3.0.co;2-o
Subject(s) - van hove singularity , pairing , cuprate , condensed matter physics , superconductivity , physics , singularity , exponent , density of states , wave function , essential singularity , s wave , order (exchange) , quantum mechanics , mathematics , fermi level , gravitational singularity , mathematical analysis , linguistics , philosophy , finance , geophysics , economics , electron
Using Gorkov's description of weakly coupled superconductors, together with a tight‐binding model on two‐dimensional lattices, we derive a pair of coupled equations for the mixed (s + i d)‐wave order parameters. It is shown that only in a small parameter region both the s‐ and d‐wave states coexist with each other, whose order parameters have been obtained as a function of temperature. For the d‐wave pairing, the van Hove singularity in the density of states is found to have more evident effect on enhancing the superconducting transition temperature and reducing the isotope‐mass exponent, and thereby is more favorable to accounting for experimental data in cuprate superconductors.