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Signature of a randomness-driven spin-liquid state in a frustrated magnet

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 نشر من قبل Panchanan Khuntia
 تاريخ النشر 2021
  مجال البحث فيزياء
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Collective behaviour of electrons, frustration induced quantum fluctuations and entanglement in quantum materials underlie some of the emergent quantum phenomena with exotic quasi-particle excitations that are highly relevant for technological applications. Frustrated quantum materials offer an exciting venue to realize highly entangled quantum states with fractional excitations. Herein, we present our thermodynamic and muon spin relaxation measurements on the recently synthesized frustrated antiferromagnet Li4CuTeO6, in which Cu2+ ions (S = 1/2) constitute a disordered triangular-lattice in the crystallographic ab-plane. Our experiments detect neither long-range magnetic ordering nor spin freezing down to a temperature of 1.55 K despite the presence of strong antiferromagnetic interaction between Cu2+ moments leading to a large Curie-Weiss temperature of -163 K. Muon spin relaxation results demonstrate a dynamic liquid-like quantum state. The temperature and magnetic field scaling of magnetization and specific heat reveal a data collapse pointing towards the presence of random-singlets within a disorder-driven correlated and dynamic ground-state in this frustrated antiferromagnet.

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