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arXiv · 1611.00967

Quantum ferromagnet in the proximity of the tricritical point

Petr Opletal·Jan Prokleška·Jaroslav Valenta·Petr Proschek·Vladimír Tkáč·Róbert Tarasenko·Marie Běhounková·Šárka Matoušková·Mohsen M. Abd-Elmeguid·Vladimír Sechovský
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Abstract

Echoes of quantum phase transitions (QPTs) at finite temperatures are theoretically and experimentally challenging and unexplored topics. Particularly in metallic quantum ferromagnets the experimental investigations are hampered by an intricate preparation of sufficiently pure samples and the access to the proper coordinates in parameter space. The present study shows that it is possible to tune a specific system at easily accessible conditions to the vicinity of its quantum phase transition. The physics is demonstrated on Ru-doped UCoAl, driven by pressure or substitution to and across the tricritical point and follows the first-order transition line to the theoretically presumed QPT. These findings open the possibilities for further in-depth studies of classical and quantum critical phenomena at easily reachable conditions.

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Petr Opletal, Jan Prokleška, Jaroslav Valenta, Petr Proschek, Vladimír Tkáč, Róbert Tarasenko, Marie Běhounková, Šárka Matoušková, Mohsen M. Abd-Elmeguid, Vladimír Sechovský. 2016-11-03. Quantum ferromagnet in the proximity of the tricritical point. https://doi.org/10.1038/s41535-017-0035-6

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