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arXiv · 2312.13140

Optimal half-metal band structure for large thermoelectric performance

Finantius E. M. Rahangiar·Adam B. Cahaya·Melania S. Muntini·Isa Anshori·Eddwi H. Hasdeo
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Abstract

Half-metal ferromagnets were predicted [in IEEE Trans. Mag. 51, 1 (2015)] to give large thermoelectric performance in anti-parallel spin valve configuration. Despite being metals that suffer from the Wiedemann-Franz law, the additional spin degrees of freedom allow for tuning of the thermoelectric properties due to the spin-valve enhancement factor (SVEF). We test this theory and find a mismatch of parameters that gives large TE performance and large SVEF. As a result, we show that the spin-valve setup is useful only for gapless HMF with initially poor TE performance. To obtain the largest TE performance, one still needs to open the band gap.

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Finantius E. M. Rahangiar, Adam B. Cahaya, Melania S. Muntini, Isa Anshori, Eddwi H. Hasdeo. 2023-12-20. Optimal half-metal band structure for large thermoelectric performance. https://doi.org/10.1103/physrevb.110.035150

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