Singularities of the order parameter of a superconductor

Journal Article · Thu May 01 04:00:00 EDT 1980 · Sov. Phys. - JETP (Engl. Transl.); (United States)

OSTI ID:6712877

Makarov, V I

It is shown that in the general case the singularities of ..delta..(p,..omega..) in p,..omega.. space are due to changes in the topology of the line of intersection of the Fermi surface -(p)=-/sub F/ with the equal-energy phonon surfaces ..omega../sub lambda/(q)=..omega... The singularities of the averaged quantity ..delta..(..omega..)=<..delta..(p,..omega..)>/sub p/ are the consequences of the singularities in ..delta..(p,..omega..). The function ..delta..(..omega..) can have singularities of two types. The first is due to the fact that at a definite value p=p* the surfaces -(p*+q)=-/sub F/ and ..omega../sub lambda/(q)=..omega.. are tangent at the point q=q/sub c/, where the vector q/sub c/ satisfies the conditions of Kohn singularity for the surfaces -(p*)=-/sub F/ and -(p*+q/sub c/)=-/sub F/. The second type of singularity of ..delta..(..omega..) exists if the surface ..omega../sub lambda/(q)=..omega.. changes its topology at some value q=q/sub k/, while the surfaces -(p)=-/sub F/ and -(p+q/sub k/)=-/sub F/ intersect or are tangent.

• Research Organization: Khar'kov Physicotechnical Institute, Ukrainian Academy of Sciences
• OSTI ID: 6712877
• Journal Information: Sov. Phys. - JETP (Engl. Transl.); (United States), Journal Name: Sov. Phys. - JETP (Engl. Transl.); (United States) Vol. 51:5; ISSN SPHJA
• Country of Publication: United States
• Language: English

Related Subjects

656100* -- Condensed Matter Physics-- Superconductivity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ENERGY LEVELS
FERMI LEVEL
MATHEMATICS
ORDER PARAMETERS
PHONONS
QUASI PARTICLES
SINGULARITY
SUPERCONDUCTORS
TOPOLOGY