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arXiv · 1207.6469

Singlet Ground State of the Quantum Antiferromagnet Ba3CuSb2O9

J. A. Quilliam·F. Bert·E. Kermarrec·C. Payen·C. Guillot-Deudon·P. Bonville·C. Baines·H. Luetkens·P. Mendels
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Abstract

We present local probe results on the honeycomb lattice antiferromagnet Ba3CuSb2O9. Muon spin relaxation measurements in zero field down to 20 mK show unequivocally that there is a total absence of spin freezing in the ground state. Sb NMR measurements allow us to track the intrinsic susceptibility of the lattice, which shows a maximum at around 55 K and drops to zero in the low-temperature limit. The spin-lattice relaxation rate shows two characteristic energy scales, including a field-dependent crossover to exponential low-temperature behavior, implying gapped magnetic excitations.

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J. A. Quilliam, F. Bert, E. Kermarrec, C. Payen, C. Guillot-Deudon, P. Bonville, C. Baines, H. Luetkens, P. Mendels. 2012-07-27. Singlet Ground State of the Quantum Antiferromagnet Ba3CuSb2O9. https://doi.org/10.1103/physrevlett.109.117203

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