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arXiv · 1607.03298

$μ$SR evidence for the U(1) quantum spin liquid ground state in the triangular antiferromagnet YbMgGaO$_4$

Yuesheng Li·Devashibhai Adroja·Pabitra K. Biswas·Peter J. Baker·Qian Zhang·Juanjuan Liu·Alexander A. Tsirlin·Philipp Gegenwart·Qingming Zhang
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Abstract

Muon spin relaxation and rotation ($μ$SR) experiments on single crystals of the structurally perfect triangular antiferromagnet YbMgGaO$_4$ indicate the absence of both static long-range magnetic order and spin freezing down to 0.048 K in zero field. Below 0.4 K, the $μ^{+}$ spin relaxation rates, which are proportional to the dynamic correlation function of the Yb$^{3+}$ spins,exhibit temperature-independent plateaus. Same behavior is revealed by temperature-independent local susceptibilities extracted from the Knight shifts of the $μ^{+}$ spin rotation frequencies under a transverse field of 20 Oe. All these $μ$SR results unequivocally support the formation of a gapless U(1) quantum spin liquid ground state in the triangular antiferromagnet YbMgGaO$_4$.

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Yuesheng Li, Devashibhai Adroja, Pabitra K. Biswas, Peter J. Baker, Qian Zhang, Juanjuan Liu, Alexander A. Tsirlin, Philipp Gegenwart, Qingming Zhang. 2016-07-12. $μ$SR evidence for the U(1) quantum spin liquid ground state in the triangular antiferromagnet YbMgGaO$_4$. https://doi.org/10.1103/physrevlett.117.097201

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