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arXiv · 2109.03738

Propagation of longitudinal acoustic phonons in ZrTe$_{\boldsymbol{5}}$ exposed to a quantizing magnetic field

Toni Ehmcke·Stanislaw Galeski·Denis Gorbunov·Sergei Zherlitsyn·Joachim Wosnitza·Johannes Gooth·Tobias Meng
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Abstract

The compound ZrTe$_5$ has recently been connected to a charge-density-wave (CDW) state with intriguing transport properties. Here, we investigate quantum oscillations in ultrasound measurements that microscopically originate from electron-phonon coupling and analyze how these would be affected by the presence or absence of a CDW. We calculate the phonon self-energy due to electron-phonon coupling, and from there deduce the sound-velocity renormalization and sound attenuation. We find that the theoretical predictions for a metallic Dirac model resemble the experimental data on a quantitative level for magnetic fields up to the quantum-limit regime.

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Toni Ehmcke, Stanislaw Galeski, Denis Gorbunov, Sergei Zherlitsyn, Joachim Wosnitza, Johannes Gooth, Tobias Meng. 2021-11-22. Propagation of longitudinal acoustic phonons in ZrTe$_{\boldsymbol{5}}$ exposed to a quantizing magnetic field. https://doi.org/10.1103/physrevb.104.245117

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