Beyond Eliashberg Superconductivity in MgB{sub 2} : Anharmonicity, Two-Phonon Scattering, and Multiple Gaps

Journal Article · Mon Aug 20 00:00:00 EDT 2001 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.87.087005· OSTI ID:40231060

Liu, Amy Y; Mazin, I I; Kortus, Jens

Density-functional calculations of the phonon spectrum and electron-phonon coupling in MgB{sub 2} are presented. The E{sub 2g} phonons, which involve in-plane Bdisplacements, couple strongly to the p{sub x,y} electronic bands. The isotropic electron-phonon coupling constant is calculated to be about 0.8. Allowing for different order parameters in different bands, the superconducting {lambda} in the clean limit is calculated to be significantly larger. The E{sub 2g} phonons are strongly anharmonic, and the nonlinear contribution to the coupling between the E{sub 2g} modes and the p{sub x,y} bands is significant.

• Sponsoring Organization: (US)
• OSTI ID: 40231060
• Journal Information: Physical Review Letters, Vol. 87, Issue 8; Other Information: DOI: 10.1103/PhysRevLett.87.087005; Othernumber: PRLTAO000087000008087005000001; 052134PRL; PBD: 20 Aug 2001; ISSN 0031-9007
• Publisher: The American Physical Society
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ELECTRON-PHONON COUPLING
ORDER PARAMETERS
PHONONS
SCATTERING
SUPERCONDUCTIVITY