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arXiv · 1108.3705

Ferro-quadrupolar ordering in PrTi$_2$Al$_{20}$

Taku J Sato·Soshi Ibuka·Yusuke Nambu·Teruo Yamazaki·Akito Sakai·Satoru Nakatsuji
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Abstract

Origin of the non-magnetic phase transition in PrTi$_2$Al$_{20}$, reported earlier in the macroscopic study, has been asserted microscopically using elastic and inelastic neutron scattering techniques. It has been shown spectroscopically that the crystalline-electric-field ground state is a non-magnetic $Γ_3$ doublet, whereas the excited states are two triplets ($Γ_4$ and $Γ_5$) and a singlet ($Γ_1$). The diffraction experiment under external magnetic field shows that the non-magnetic transition is indeed ferro-quadrupolar ordering, which takes place as a consequence of cooperative removal of the ground-state-doublet degeneracy. It is therefore concluded that PrTi$_2$Al$_{20}$ is another rare example of Pr compounds exhibiting non-magnetic quadrupolar order.

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Taku J Sato, Soshi Ibuka, Yusuke Nambu, Teruo Yamazaki, Akito Sakai, Satoru Nakatsuji. 2011-08-18. Ferro-quadrupolar ordering in PrTi$_2$Al$_{20}$. https://doi.org/10.1103/physrevb.86.184419

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