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arXiv · 1804.10487

High-pressure Raman study on the superconducting pyrochlore oxide Cd2Re2O7

Yasuhito Matsubayashi·Takumi Hasegawa·Norio Ogita·Jun-ichi Yamaura·Zenji Hiroi
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Abstract

The superconducting pyrochlore oxide Cd2Re2O7 (Tc = 1 K), which is now considered as a candidate of the spin-orbit-coupled metal, shows an inversion-symmetry-breaking structural transition at Ts1 = 200 K. Ts1 decreases with increasing pressure and disappears at around Pc = 4:2GPa, where at least four high-pressure phases with tiny structural distortions are suggested by means of powder X-ray diffraction [Yamaura PRB 2017]. We have carried out Raman scattering experiments to investigate changes in the crystal symmetry under high pressures up to 4.8 GPa. A structural transition at 1.9-3.0 GPa and the recovery of inversion symmetry above Pc are observed at 12 K.

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Yasuhito Matsubayashi, Takumi Hasegawa, Norio Ogita, Jun-ichi Yamaura, Zenji Hiroi. 2018-04-27. High-pressure Raman study on the superconducting pyrochlore oxide Cd2Re2O7. https://doi.org/10.1016/j.physb.2017.10.030

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