Realization of U(1) Dirac Quantum Spin Liquid in YbZn2GaO5

• DOI: 10.48550/arxiv.2305.20040
• Publication Date: 2023-01-01
• Authors: Sijie Xu; Rabindranath Bag; Nicholas E. Sherman; Lalit Yadav; А. И. Колесников; A. Podlesnyak; Joel E. Moore; Sara Haravifard
• Keywords: Spinon; Brillouin zone; Spin wave; State of matter

The emergence of a quantum spin liquid (QSL), state matter that can result when electron spins are highly correlated but do not become ordered, has been the subject considerable body research in condensed physics. Spin states have proposed as hosts for high-temperature superconductivity and host topological properties with potential applications information science. excitations most liquids conventional waves rather quasiparticles known spinons, whose existence is well established experimentally only one-dimensional systems; unambiguous experimental realization QSL behavior higher dimensions remains challenging. Here we investigate novel compound YbZn2GaO5, which an ideal triangular lattice effective spin-1/2 moments no inherent chemical disorder. Thermodynamic inelastic neutron scattering (INS) measurements performed on high-quality single crystal samples YbZn2GaO5 exclude possibility long-range magnetic ordering down to 60 mK, demonstrate quadratic power law heat capacity reveal continuum parts Brillouin zone. Both low-temperature thermodynamics INS spectra suggest U(1) Dirac gapless spinon concentrated at certain points zone, additional features also consistent theoretical expectations lattice.