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arXiv · 1912.09692

Mott and spin-Peierls physics in TiPO$_4$ under high pressure

H. Johan M. Jönsson·Marcus Ekholm·Silke Biermann·Maxim Bykov·Igor A. Abrikosov
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Abstract

TiPO$_4$ is a Mott insulator and one of few inorganic compounds featuring a spin-Peierls phase at low temperature. Recent experimental studies have suggested the presence of spin-Peierls dimerization also at ambient temperature though at high pressure. Here, we present a combined experimental and theoretical study of the energetics of the high-pressure phase. We analyse dimerization properties and their coupling to spin degrees of freedom. Most importantly, we argue that TiPO$_4$ resents a direct analogue to the celebrated binary transition metal oxide VO$_2$. TiPO$_4$ allows to assess spin-dimer physics in the high-pressure regime in a controlled fashion, having the potential to become an important model system representative of the class of dimerized transition metal oxides.

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H. Johan M. Jönsson, Marcus Ekholm, Silke Biermann, Maxim Bykov, Igor A. Abrikosov. 2019-12-20. Mott and spin-Peierls physics in TiPO$_4$ under high pressure. https://arxiv.org/abs/1912.09692

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