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arXiv · 1601.05071

Candidate quantum spin ice in the pyrochlore Pr$_2$Hf$_2$O$_7$

Romain Sibille·Elsa Lhotel·Monica Ciomaga Hatnean·Geetha Balakrishnan·Björn Fåk·Nicolas Gauthier·Tom Fennell·Michel Kenzelmann
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Abstract

We report the low temperature magnetic properties of the pyrochlore Pr$_2$Hf$_2$O$_7$. Polycrystalline and single-crystal samples are investigated using time-of-flight neutron spectroscopy and macroscopic measurements, respectively. The crystal-field splitting produces a non-Kramers doublet ground state for Pr$^{3+}$, with Ising-like anisotropy. Below 0.5 K ferromagnetic correlations develop, which suggests that the system enters a spin ice-like state associated with the metamagnetic behavior observed at $μ_0H_c\sim2.4$~T. In this regime, the development of a discrete inelastic excitation in the neutron spectra indicates the appearance of spin dynamics which are likely related to cooperative quantum fluctuations.

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Romain Sibille, Elsa Lhotel, Monica Ciomaga Hatnean, Geetha Balakrishnan, Björn Fåk, Nicolas Gauthier, Tom Fennell, Michel Kenzelmann. 2016-08-12. Candidate quantum spin ice in the pyrochlore Pr$_2$Hf$_2$O$_7$. https://doi.org/10.1103/physrevb.94.024436

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