Pressure-tuning of electronic structure of CeTe3 probed by femtosecond collective mode spectroscopy

Chandra V. Kotyada; Priyanka Yogi; Amon P. Lanz; Rolf Heid; Jonas Tauch; Manuel Obergfell; Hanjo Schaefer; Paula Giraldo-Gallo; Ian R. Fisher; Alexej Pashkin; Jure Demsar

arXiv · 2608.20057

Pressure-tuning of electronic structure of CeTe3 probed by femtosecond collective mode spectroscopy

Chandra V. Kotyada·Priyanka Yogi·Amon P. Lanz·Rolf Heid·Jonas Tauch·Manuel Obergfell·Hanjo Schaefer·Paula Giraldo-Gallo·Ian R. Fisher·Alexej Pashkin·Jure Demsar

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Abstract

We use femtosecond optical spectroscopy to study the evolution of coherent order-parameter dynamics in the prototypical charge-density-wave (CDW) system CeTe3 under hydrostatic pressure. The CDW transition temperature decreases from approximately 570 K at ambient pressure to near room temperature at approximately 6 GPa. The pressure dependence of the order-parameter recovery dynamics indicates enhanced electron-phonon coupling with increasing pressure, implying that CDW suppression is driven predominantly by the reduction in Fermi-surface nesting. Above 7 GPa, no evidence of CDW order is observed down to cryogenic temperatures. Concurrently, the relaxation dynamics exhibit significant slowing down at low-temperatures, consistent with emerging heavy-electron behaviour due to pressure-enhanced hybridization between localized Ce 4f levels and itinerant carriers.

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Chandra V. Kotyada, Priyanka Yogi, Amon P. Lanz, Rolf Heid, Jonas Tauch, Manuel Obergfell, Hanjo Schaefer, Paula Giraldo-Gallo, Ian R. Fisher, Alexej Pashkin, Jure Demsar. 2026-08-20. Pressure-tuning of electronic structure of CeTe3 probed by femtosecond collective mode spectroscopy. https://arxiv.org/abs/2608.20057

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