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arXiv · 2004.01201

Thermal and field-induced transitions in ferroquadrupolar Kondo systems

Frederic Freyer·SungBin Lee·Yong Baek Kim·Simon Trebst·Arun Paramekanti
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Abstract

Recent experiments have examined the impact of a magnetic field on ferroquadrupolar orders in the intermetallic Kondo material PrTi$_2$Al$_{20}$. Motivated by this, we use extensive Monte Carlo simulations to study a diamond lattice XY model of non-Kramers pseudospin-$1/2$ Pr$^{3+}$ moments which crucially incorporates three-spin interactions. This model supports a thermal $Z_3$ Potts ordering transition upon cooling from the paramagnetic phase into the ferroquadrupolar phase. An applied magnetic field along the [110] direction leads to a thermal Ising transition out of the quadrupolar ordered phase. A magnetic field along the [001] direction leads to only thermal crossovers, but supports a spinodal transition out of metastable domains which could be strongly pinned by coupling to elastic lattice deformations. We propose noise measurements as a potential probe to "hear" the spinodal transition. Our work highlights the importance of multispin interactions in Kondo materials near the small-to-large Fermi surface transition.

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Frederic Freyer, SungBin Lee, Yong Baek Kim, Simon Trebst, Arun Paramekanti. 2020-04-02. Thermal and field-induced transitions in ferroquadrupolar Kondo systems. https://doi.org/10.1103/physrevresearch.2.033176

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