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arXiv · 2209.08474

Superparamagnetic and metal-like Ru2TiGe: a propitious thermoelectric material

Sanchayita Mondal·Krishanu Ghosh·R. Ranganathan·Eric Alleno·Chandan Mazumdar
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Abstract

We report a study of structural, magnetic, heat capacity and thermoelectric properties of a Rubased Heusler alloy, Ru2TiGe. The magnetic measurements reveal that at higher temperatures, diamagnetic and Pauli paramagnetic contributions dominate the magnetic behaviour whereas, at lower temperatures (T<= 20 K), superparamagnetic interaction among clusters is observed. Effect of such magnetic defects is also evident in the electrical resistivity behaviour at lower temperatures. Though the temperature dependence of resistivity exhibits a metal-like nature, the large value of Seebeck coefficient leads to an appreciable power factor of the order of 1 mW/mK2 at 300 K. Large power factor as well as low thermal conductivity results in a value of ZT = 0.025 at 390 K for Ru2TiGe that is orders of magnitude higher than that of the other pure Heusler alloys and point towards its high potential for practical thermoelectric applications.

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Sanchayita Mondal, Krishanu Ghosh, R. Ranganathan, Eric Alleno, Chandan Mazumdar. 2022-09-18. Superparamagnetic and metal-like Ru2TiGe: a propitious thermoelectric material. https://doi.org/10.1016/j.jallcom.2023.171050

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