Terahertz spectroscopic evidence of electron correlations in SrVO 3 epitaxial thin films.

Electron correlation in transition metal oxides (TMOs) is an intriguing topic in condensed matter physics, revealing a wide variety of exotic physical properties. Investigating low-energy carrier dynamics by terahertz (THz) spectroscopy is an efficient route to obtain the essential insights into electron correlation. In the present study, THz-time-domain spectroscopy is employed to probe electron correlation in SrVO ₃ epitaxial thin films. The low energy carrier dynamics of SrVO ₃ in the range of 0.2-6.0 meV shows a typical metallic behavior as overserved in dc transport measurements. The obtained temperature-dependent optical parameters provide evidence of mass renormalization in the low energy regime and carrier momentum relaxation happens via the electron-electron scattering mechanism. Overall, the frequency and temperature-dependent optical parameters indicate the Fermi liquid ground state in a Mott-Hubbard type correlated metal SrVO ₃ thin film. Our results provide significant insight on low energy carrier dynamics in the correlated electron system, particularly perovskite-based d ¹ TMOs.
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