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arXiv · 2001.07420

Helimagnetic Structure and Heavy-Fermion-Like Behavior in the Vicinity of the Quantum Critical Point in Mn$_3$P

H. Kotegawa·M. Matsuda·F. Ye·Y. Tani·K. Uda·Y. Kuwata·H. Tou·E. Matsuoka·H. Sugawara·T. Sakurai·H. Ohta·H. Harima·K. Takeda·J. Hayashi·S. Araki·T. C. Kobayashi
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Abstract

Antiferromagnet Mn$_3$P with Neel temperature $T_N=30$ K is composed of Mn-tetrahedrons and zigzag chains formed by three inequivalent Mn sites. Due to the nearly frustrated lattice with many short Mn-Mn bonds, competition of the exchange interactions is expected. We here investigate the magnetic structure and physical properties including pressure effect in single crystals of this material, and reveal a complex yet well-ordered helimagnetic structure. The itinerant character of this materials is strong, and the ordered state with small magnetic moments is easily suppressed under pressure, exhibiting a quantum critical point at $\sim1.6$ GPa. The remarkable mass renormalization, even in the ordered state, and an incoherent-coherent crossover in the low-temperature region, characterize an unusual electronic state in Mn$_3$P, which is most likely effected by the underlying frustration effect.

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H. Kotegawa, M. Matsuda, F. Ye, Y. Tani, K. Uda, Y. Kuwata, H. Tou, E. Matsuoka, H. Sugawara, T. Sakurai, H. Ohta, H. Harima, K. Takeda, J. Hayashi, S. Araki, T. C. Kobayashi. 2020-01-21. Helimagnetic Structure and Heavy-Fermion-Like Behavior in the Vicinity of the Quantum Critical Point in Mn$_3$P. https://doi.org/10.1103/physrevlett.124.087202

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