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arXiv · 2310.18115

Temperature-dependent generalized ellipsometry of the metal-insulator phase transition in low-symmetry charge-transfer salts

Achyut Tiwari·Bruno Gompf·Martin Dressel
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Abstract

Determining the optical and electronic properties of strongly anisotropic materials with symmetries below orthorhombic remains challenging; generalized ellipsometry is a powerful technique in this regard. Here, we employ Mueller matrix spectroscopic and temperature-dependent ellipsometry to determine the frequency dependence of six components of the dielectric-function tensor of the two-dimensional charge-transfer salt $\alpha$-(BEDT-TTF)$_2$I$_3$ across its metal-insulator transition. Our results offer valuable insights into temperature-dependent changes of the components of the spectroscopic dielectric-function tensor across the metal-insulator transition. This advanced method allows extension to other electronic transitions.

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Achyut Tiwari, Bruno Gompf, Martin Dressel. 2023-10-27. Temperature-dependent generalized ellipsometry of the metal-insulator phase transition in low-symmetry charge-transfer salts. https://doi.org/10.1063/5.0215647

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