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arXiv · 2002.07960

Pressure-Induced Restoration of the Reversed Crystal-Field Splitting in $\alpha$-Sr$_2$CrO$_4$

Ryo Takahashi·Tomoki Yamaguchi·Koudai Sugimoto·Touru Yamauchi·Hiroya Sakurai·Yukinori Ohta
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Abstract

Motivated by an experimental finding that the successive phase transitions in $\alpha$-Sr$_2$CrO$_4$ observed at ambient pressure ceases to exist under high pressures, we carry out the density-functional-theory-based electronic structure calculations and demonstrate that the reversal of the crystal-field splitting reported previously is restored under high pressures, so that the orbital degrees of freedom disappears, resulting in the single phase transition that divides the system into high-temperature Mott insulating and low-temperature antiferromagnetic insulating phases.

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Ryo Takahashi, Tomoki Yamaguchi, Koudai Sugimoto, Touru Yamauchi, Hiroya Sakurai, Yukinori Ohta. 2020-02-19. Pressure-Induced Restoration of the Reversed Crystal-Field Splitting in $\alpha$-Sr$_2$CrO$_4$. https://doi.org/10.7566/jpscp.30.011026

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