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arXiv · 1310.5105

Connecting electron and phonon spectroscopy data to consistently determine quasiparticle-phonon coupling on the surface of topological insulators

Colin Howard·M. El-Batanouny
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Abstract

Photoemission and phonon spectroscopies have yielded widely varying estimates of the electron-phonon coupling constant λ on the surfaces of topological insulators, even for a particular material and technique. We connect the results of these experiments by determining the Dirac fermion quasiparticle spectral function using information from measured spectra of a strongly-interacting, low-lying optical surface phonon band. The manifest spectral features resulting from the coupling are found to vary on energy scales < 1 meV, and are distinct from those traditionally observed in the case of acoustic phonons in metals. We explore different means of determining λ from the electron perspective and identify definitions that yield values consistent with phonon spectroscopy.

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Colin Howard, M. El-Batanouny. 2013-10-21. Connecting electron and phonon spectroscopy data to consistently determine quasiparticle-phonon coupling on the surface of topological insulators. https://doi.org/10.1103/physrevb.89.075425

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