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arXiv · 1610.03200

NMR Observation of Ferro-quadrupole Order in PrTi2Al20

Takanori Taniguchi·Makoto Yoshida·Hikaru Takeda·Masashi Takigawa·Masaki Tsujimoto·Akito Sakai·Yosuke Matsumoto·Satoru Nakatsuji
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Abstract

We report the results of 27Al-NMR measurements on a single crystal of PrTi2Al20. This compound shows a phase transition near 2 K associated with the quadrupole degree of freedom of Pr ions, for which the ground state of the crystalline electric field is a nonmagnetic doublet. When a magnetic field is applied along the <111> direction, the NMR lines split upon entering the low-temperature phase, indicating the breaking of the three fold rotation symmetry due to the field-induced magnetic dipole perpendicular to the field. This provides microscopic evidence for a ferro order of the O20 quadrupole. Although a first-order transition is expected theoretically, the line splitting evolves continuously within the experimental resolution.

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Takanori Taniguchi, Makoto Yoshida, Hikaru Takeda, Masashi Takigawa, Masaki Tsujimoto, Akito Sakai, Yosuke Matsumoto, Satoru Nakatsuji. 2016-10-11. NMR Observation of Ferro-quadrupole Order in PrTi2Al20. https://doi.org/10.7566/jpsj.85.113703

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