Recent progress on magnetic-field studies on quantum-spin-liquid candidates

Abstract

Quantum spin liquids (QSLs) represent a novel state of matter in which\nquantum fluctuations prevent conventional magnetic order from being\nestablished, and the spins remain disordered even at zero temperature. There\nhave been many theoretical developments proposing various QSL states. On the\nother hand, experimental movement was relatively slow largely due to\nlimitations on the candidate materials and difficulties in the measurements. In\nrecent years, the experimental progress has been accelerated. In this topical\nreview, we give a brief summary of experiments on the QSL candidates under\nmagnetic fields. We arrange our discussions by two categories: i)\nGeometrically-frustrated systems, including triangular-lattice compounds\nYbMgGaO4 and YbZnGaO4, kappa-(BEDT-TTF)2Cu2(CN)3, and EtMe3Sb[Pd(dmit)2]2, and\nkagome system ZnCu3(OH)6Cl2; ii) the Kitaev material alpha-RuCl3. Among these,\nwe will pay special attention to alpha-RuCl3, which has been intensively\nstudied by our and other groups recently. We will present evidence that both\nsupports and unsupports the QSL ground state for these materials, based on\nwhich we give several perspectives to stimulate further research activities.\n