Extreme electron-phonon coupling in boron-based layered superconductors

Authors

J. M. An, Lawrence Berkeley National Laboratory
S. Y. Savrasov, New Jersey Institute of Technology
H. Rosner, University of California, Davis
W. E. Pickett, University of California, Davis

Document Type

Article

Publication Date

12-1-2002

Abstract

The phonon-mode decomposition of the electron-phonon coupling in the MgB2-like system Li1-xBC is explored using first-principles calculations. It is found that the high-temperature superconductivity of such systems results from extremely strong coupling up to only ∼2% of the phonon modes. Noteworthy characteristics of E2g branches include (1) "mode λ" values of 25 and greater compared to a mean of ∼0.4 for other modes, (2) a precipitous Kohn anomaly, and (3) E2g phonon linewidths within a factor of ∼2 of the frequency itself, indicating impending breakdown of conventional electron-phonon theory. This behavior in borne out by recent inelastic x-ray scattering studies of MgB2 by Shukla et al.

Identifier

0036970495 (Scopus)

Publication Title

Physical Review B Condensed Matter and Materials Physics

ISSN

01631829

First Page

2205021

Last Page

2205024

Issue

22

Volume

66

Recommended Citation

An, J. M.; Savrasov, S. Y.; Rosner, H.; and Pickett, W. E., "Extreme electron-phonon coupling in boron-based layered superconductors" (2002). Faculty Publications. 14550.
https://digitalcommons.njit.edu/fac_pubs/14550