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arXiv · 1506.04527

Origin of modulated phases and magnetic hysteresis in TmB_4

Keola Wierschem·Sai Swaroop Sunku·Tai Kong·Toshimitsu Ito·Paul C. Canfield·Christos Panagopoulos·Pinaki Sengupta
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Abstract

We investigate the low temperature magnetic phases in TmB_4, a metallic quantum magnet on the geometrically frustrated Shastry-Sutherland lattice, using co-ordinated experimental and theoretical studies. Our results provide an explanation for the appearance of the intriguing fractional plateau in TmB_4 and accompanying magnetic hysteresis. Together with observation of the bump in the half-plateau, our results support the picture that the magnetization plateau structure in TmB_4 is strongly influenced by the zero-field modulated phases. We present a phenomenological model to explain the appearance of the modulated phases and a microscopic Hamiltonian that captures the complete magnetic behavior of TmB_4.

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Keola Wierschem, Sai Swaroop Sunku, Tai Kong, Toshimitsu Ito, Paul C. Canfield, Christos Panagopoulos, Pinaki Sengupta. 2015-06-15. Origin of modulated phases and magnetic hysteresis in TmB_4. https://doi.org/10.1103/physrevb.92.214433

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