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arXiv · 2011.06358

Hot carrier-assisted switching of the electron-phonon interaction in 1$T$-VSe$_2$

Paulina Majchrzak·Sahar Pakdel·Deepnarayan Biswas·Alfred J. H. Jones·Klara Volckaert·Igor Marković·Federico Andreatta·Raman Sankar·Chris Jozwiak·Eli Rotenberg·Aaron Bostwick·Charlotte E. Sanders·Yu Zhang·Gabriel Karras·Richard T. Chapman·Adam Wyatt·Emma Springate·Jill A. Miwa·Philip Hofmann·Phil D. C. King·Nicola Lanata·Young Jun Chang·Søren Ulstrup
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Abstract

We apply an intense infrared laser pulse in order to perturb the electronic and vibrational states in the three-dimensional charge density wave material 1$T$-VSe$_2$. Ultrafast snapshots of the light-induced hot carrier dynamics and non-equilibrium quasiparticle spectral function are collected using time- and angle-resolved photoemission spectroscopy. The hot carrier temperature and time-dependent electronic self-energy are extracted from the time-dependent spectral function, revealing that incoherent electron-phonon interactions heat the lattice above the charge density wave critical temperature on a timescale of $(200 \pm 40)$~fs. Density functional perturbation theory calculations establish that the presence of hot carriers alters the overall phonon dispersion and quenches efficient low-energy acoustic phonon scattering channels, which results in a new quasi-equilibrium state that is experimentally observed.

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Paulina Majchrzak, Sahar Pakdel, Deepnarayan Biswas, Alfred J. H. Jones, Klara Volckaert, Igor Marković, Federico Andreatta, Raman Sankar, Chris Jozwiak, Eli Rotenberg, Aaron Bostwick, Charlotte E. Sanders, Yu Zhang, Gabriel Karras, Richard T. Chapman, Adam Wyatt, Emma Springate, Jill A. Miwa, Philip Hofmann, Phil D. C. King, Nicola Lanata, Young Jun Chang, Søren Ulstrup. 2020-11-12. Hot carrier-assisted switching of the electron-phonon interaction in 1$T$-VSe$_2$. https://doi.org/10.1103/physrevb.103.l241108

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