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arXiv · 1809.01947

NaYbS$_2$ - a new planar spin-$\frac{1}{2}$ triangular-lattice magnet and putative spin liquid

M. Baenitz·Ph. Schlender·J. Sichelschmidt·Y. A. Onykiienko·Z. Zangeneh·K. M. Ranjith·R. Sarkar·L. Hozoi·H. C. Walker·J. -C. Orain·H. Yasuoka·J. van den Brink·H. H. Klauss·D. S. Inosov·Th. Doert
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Abstract

Platelike high-quality NaYbS$_{2}$ rhombohedral single crystals with lateral dimensions of a few mm have been grown and investigated in great detail by bulk methods like magnetization and specific heat, but also by local probes like nuclear magnetic resonance (NMR), electron-spin resonance (ESR), muon-spin relaxation ($\mu$SR), and inelastic neutron scattering (INS) over a wide field and temperature range. Our single-crystal studies clearly evidence a strongly anisotropic quasi-2D magnetism and an emerging spin-orbit entangled $S=1/2$ state of Yb towards low temperatures together with an absence of long-range magnetic order down to 260~mK. In particular, the clear and narrow Yb ESR lines together with narrow $^{23}$Na NMR lines evidence an absence of inherent structural distortions in the system, which is in strong contrast to the related spin-liquid candidate YbMgGaO$_{4}$ falling within the same space group $R\overline{3}m$. This identifies NaYbS$_{2}$ as a rather pure spin-1/2 triangular lattice magnet and a new putative quantum spin liquid.

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M. Baenitz, Ph. Schlender, J. Sichelschmidt, Y. A. Onykiienko, Z. Zangeneh, K. M. Ranjith, R. Sarkar, L. Hozoi, H. C. Walker, J. -C. Orain, H. Yasuoka, J. van den Brink, H. H. Klauss, D. S. Inosov, Th. Doert. 2018-09-06. NaYbS$_2$ - a new planar spin-$\frac{1}{2}$ triangular-lattice magnet and putative spin liquid. https://doi.org/10.1103/physrevb.98.220409

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