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Signatures of polaronic excitations in quasi-one-dimensional LaTiO$_{3.41}$

C. A. Kuntscher·M. Dressel·F. Lichtenberg·J. Mannhart·D. van der Marel
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Abstract

The optical properties of quasi-one-dimensional metallic LaTiO$_{3.41}$ are studied for the polarization along the $a$ and $b$ axes. With decreasing temperature modes appear along both directions suggestive for a phase transition. The broadness of these modes along the conducting axis might be due to the coupling of the phonons to low-energy electronic excitations across an energy gap. We observe a pronounced midinfrared band with a temperature dependence consistent with (interacting) polaron models. The polaronic picture is corroborated by the presence of strong electron-phonon coupling and the temperature dependence of the dc conductivity.

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C. A. Kuntscher, M. Dressel, F. Lichtenberg, J. Mannhart, D. van der Marel. 2003-01-20. Signatures of polaronic excitations in quasi-one-dimensional LaTiO$_{3.41}$. https://doi.org/10.1103/physrevb.67.035105

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