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arXiv · 2411.13954

Light-induced renormalization of the band structure of chiral tellurium

G. Gatti·N. Tancogne-Dejean·H. Hübener·U. De Giovannini·J. Dai·S. Polishchuk·Ph. Bugnon·F. Frassetto·L. Poletto·M. Chergui·M. Grioni·A. Rubio·M. Puppin·A. Crepaldi
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Abstract

Chirality in tellurium derives from a Peierls distortion driven by strong electron-phonon coupling, making this material a unique candidate for observing a light-induced topological phase transition. By using time- and angle-resolved photoelectron spectroscopy (trARPES), we reveal that upon near-infrared photoexcitation the Peierls gap is modulated by displacively excited coherent phonons with $\mathrm{A_{1g}}$ symmetry as well as chiral-symmetry-breaking $\mathrm{E'_{LO}}$ modes. By comparison with state-of-the-art TDDFT+U calculations, we reveal the microscopic origin of the in-phase oscillations of band edges, due to phonon-induced modulation of the effective Hubbard $U$ term.

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G. Gatti, N. Tancogne-Dejean, H. Hübener, U. De Giovannini, J. Dai, S. Polishchuk, Ph. Bugnon, F. Frassetto, L. Poletto, M. Chergui, M. Grioni, A. Rubio, M. Puppin, A. Crepaldi. 2024-11-21. Light-induced renormalization of the band structure of chiral tellurium. https://doi.org/10.1103/physrevmaterials.8.125001

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