TY - JOUR
T1 - Successive spatial symmetry breaking under high pressure in the spin-orbit-coupled metal C d 2 R e 2 O 7
AU - Yamaura, Jun Ichi
AU - Takeda, Keiki
AU - Ikeda, Yoichi
AU - Hirao, Naohisa
AU - Ohishi, Yasuo
AU - Kobayashi, Tatsuo C.
AU - Hiroi, Zenji
N1 - Funding Information:
The synchrotron radiation experiments were performed with the approval of JASRI (Grant No. 2011A1184). This work was supported by MEXT Elements Strategy Initiative to Form Core Research Center and also by JSPS KAKENHI (Grant No. 16K05434).
Publisher Copyright:
© 2017 American Physical Society.
PY - 2017/1/11
Y1 - 2017/1/11
N2 - The 5d-transition-metal pyrochlore oxide Cd2Re2O7, which was recently suggested to be a prototype of the spin-orbit-coupled metal [Phys. Rev. Lett. 115, 026401 (2015)10.1103/PhysRevLett.115.026401], exhibits an inversion-symmetry-breaking (ISB) transition at 200 K and a subsequent superconductivity below 1 K at ambient pressure. We study the crystal structure at high pressures up to 5 GPa by means of synchrotron x-ray powder diffraction. A rich structural phase diagram is obtained, which contains at least seven phases, and is almost consistent with the electronic phase diagram determined by previous resistivity measurements. Interestingly, the ISB transition vanishes at ∼4GPa where the enhancement of the upper critical field was observed in resistivity. Moreover, it is shown that the point groups at 8 K, probably kept in the superconducting phases, sequentially transform into piezoelectric, ferroelectric, and centrosymmetric structures on the application of pressure.
AB - The 5d-transition-metal pyrochlore oxide Cd2Re2O7, which was recently suggested to be a prototype of the spin-orbit-coupled metal [Phys. Rev. Lett. 115, 026401 (2015)10.1103/PhysRevLett.115.026401], exhibits an inversion-symmetry-breaking (ISB) transition at 200 K and a subsequent superconductivity below 1 K at ambient pressure. We study the crystal structure at high pressures up to 5 GPa by means of synchrotron x-ray powder diffraction. A rich structural phase diagram is obtained, which contains at least seven phases, and is almost consistent with the electronic phase diagram determined by previous resistivity measurements. Interestingly, the ISB transition vanishes at ∼4GPa where the enhancement of the upper critical field was observed in resistivity. Moreover, it is shown that the point groups at 8 K, probably kept in the superconducting phases, sequentially transform into piezoelectric, ferroelectric, and centrosymmetric structures on the application of pressure.
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U2 - 10.1103/PhysRevB.95.020102
DO - 10.1103/PhysRevB.95.020102
M3 - Article
AN - SCOPUS:85010410308
SN - 2469-9950
VL - 95
JO - Physical Review B
JF - Physical Review B
IS - 2
M1 - 020102
ER -