Anharmonicity and self-energy effects of the E2g phonon in MgB2

Abstract

We present a Raman scattering study of the E2g phonon anharmonicity and of superconductivity induced self-energy effects in MgB2 single crystals. We show that anharmonic two phonon decay is mainly responsible for the unusually large linewidth of the E2g mode. We observe ~ 2.5 % hardening of the E2g phonon frequency upon cooling into the superconducting state and estimate the electron-phonon coupling strength associated with this renormalization.

4 pages, 3 figures, accepted to PRB

Cited by in corpus (5)

• Observation of Leggett's collective mode in a multi-band MgB2 superconductor
• Phonon anharmonicity: a pertinent review of recent progress and perspective
• Ground state, collective mode, phase soliton and vortex in multiband superconductors
• Theory of Raman scattering from Leggett's collective mode in a multiband superconductor: Application to MgB${}_2$
• Anharmonic theory of superconductivity and its applications to emerging quantum materials