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arXiv · 1810.05360

Degeneracy of the 1/8 plateau and antiferromagnetic phases in the Shastry-Sutherland magnet TmB4

Jennifer Trinh·Sreemanta Mitra·Christos Panagopoulos·Tai Kong·Paul C. Canfield·Arthur P. Ramirez
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Abstract

The 1/8 fractional plateau phase (1/8-FPP) in Shastry-Sutherland Lattice (SSL) spin systems has been viewed an exemplar of emergence on an Archimedean lattice. Here we explore this phase in the Ising magnet TmB4 using high-resolution specific heat (C) and magnetization (M) in the field-temperature plane. We show that the 1/8-FPP is smoothly connected to the antiferromagnetic (AF) phase on ramping the field from H= 0. Thus, the 1/8-FPP is not a distinct ground state of TmB4. The implication of these results for Heisenberg spins on the SSL is discussed.

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Jennifer Trinh, Sreemanta Mitra, Christos Panagopoulos, Tai Kong, Paul C. Canfield, Arthur P. Ramirez. 2018-10-12. Degeneracy of the 1/8 plateau and antiferromagnetic phases in the Shastry-Sutherland magnet TmB4. https://doi.org/10.1103/physrevlett.121.167203

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