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arXiv · 2506.03251

Control of intervalley scattering in Bi$_2$Te$_3$ via temperature-dependent band renormalization

A. Jabed·F. Goto·B. Frimpong·D. Armanno·A. Longa·M. Michiardi·A. Damascelli·P. Hofmann·G. Jargot·H. Ibrahim·F. Légaré·N. Gauthier·S. Beaulieu·F. Boschini
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Abstract

The control of out-of-equilibrium electron dynamics in topological insulators is essential to unlock their potential in next-generation quantum technologies. However, the role of temperature on the renormalization of the electronic band structure and, consequently, on electron scattering processes is still elusive. Here, using high-resolution time- and angle-resolved photoemission spectroscopy (TR-ARPES), we show that even a modest ($\sim$15 meV) renormalization of the conduction band of Bi$_2$Te$_3$ can critically affect bulk and surface electron scattering processes. Supported by a kinetic Monte Carlo toy-model, we show that temperature-induced changes in the bulk band structure modulate the intervalley electron-phonon scattering rate, reshaping the out-of-equilibrium response. This work establishes temperature as an effective control knob for engineering scattering pathways in topological insulators.

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A. Jabed, F. Goto, B. Frimpong, D. Armanno, A. Longa, M. Michiardi, A. Damascelli, P. Hofmann, G. Jargot, H. Ibrahim, F. Légaré, N. Gauthier, S. Beaulieu, F. Boschini. 2025-06-03. Control of intervalley scattering in Bi$_2$Te$_3$ via temperature-dependent band renormalization. https://doi.org/10.1038/s41535-025-00842-8

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