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TT: Fachverband Tiefe Temperaturen
TT 39: Correlated Electrons: Charge Order
TT 39.10: Talk
Wednesday, March 20, 2024, 12:00–12:15, H 3025
The pressure-induced charge-density-wave transition in CeTe3 probed by time-resolved collective mode spectroscopy — •Priyanka Yogi1, C. Vardhan Kotyada1, J. Tauch2, H. Schäfer2, M. Obergfell1,2, D. Dominko1, A. Pashkin3, and Jure Demsar1 — 1Institute of Physics, Johannes Gutenberg University Mainz, 55128 Mainz, Germany — 2Department of Physics, University of Konstanz, Germany — 3Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
We use time-resolved optical spectroscopy to study pressure-induced charge-density-wave (CDW) phase transition in a prototype CDW system CeTe3 (T3 540 K at ambient pressure [1]). Photoinduced reflectivity traces at 300 K and ambient pressure reveal the presence of numerous oscillatory modes with frequencies between 1.2 and 4 THz. The modes display either softening or hardening as a function of pressure, yet all disappear above 5 GPa. Moreover, these modes are quenched above critical photoexcitation density. We compare the pressure and excitation density dependent mode parameters with the available temperature, chemical- and hydrostatic-pressure dependent Raman data on RTe3 series [1,2]. We show that all modes are CDW amplitude modes, a result of linear coupling between the electronic order and normal-state phonons at the CDW wavevector [3]. Thus, the studies reveal a pressure-induced transition into the metallic state taking place in CeTe3 at the critical pressure of 5 GPa at 300 K.
[1] K. Yumigeta et al., APL Mater. 10 (2022) 111112.
[1] M. Lavagnini et al., Phys. Rev. B 78 (2008) 201101.
[2] K. Warawa et al., Phys. Rev.B 108 (2023) 045147.
Keywords: RTe3; Charge density wave; collective mode spectroscopy; High pressure; Diamond anvil cell