1. Field-Induced Instability of a Gapless Spin Liquid with a Spinon Fermi Surface.
- Author
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Gomilšek, M., Klanjšek, M., Žitko, R., Pregelj, M., Bert, F., Mendels, P., Li, Y., Zhang, Q. M., and Zorko, A.
- Subjects
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GROUND state (Quantum mechanics) , *ANTIFERROMAGNETIC materials , *NUCLEAR magnetic resonance - Abstract
The ground state of the quantum kagome antiferromagnet Zn-brochantite, ZnCu3(OH)6SO4, which is one of only a few known spin-liquid (SL) realizations in two or three dimensions, has been described as a gapless SL with a spinon Fermi surface. Employing nuclear magnetic resonance in a broad magnetic-field range down to millikelvin temperatures, we show that in applied magnetic fields this enigmatic state is intrinsically unstable against a SL with a full or a partial gap. A similar instability of the gapless Fermi-surface SL was previously encountered in an organic triangular-lattice antiferromagnet, suggesting a common destabilization mechanism that most likely arises from spinon pairing. A salient property of this instability is that an infinitesimal field suffices to induce it, as predicted theoretically for some other types of gapless SLs. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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