Field-Induced Crossover of the Spin Liquid State in Triangular
The triangular antiferromagnet YbMgGaO4 is a candidate for hosting quantum
spin liquid (QSL) state, an exotic state featuring high degree of entanglement.
Lack of any spontaneous symmetry breaking or measurable local order parameter
has made experimental identification of QSL states quite stimulating.
Meanwhile, the inevitable presence of chemical disorder in real-world crystals
has driven discussion for most proposed candidates. YbMgGaO4 is no exception,
and its ground state has been the subject of heated debates. Here we report the
discovery of a field-induced crossover observed via neutron scattering and
magnetic susceptibility measurements, as well as complementary classical Monte
Carlo and Density Matrix Renormalization Group simulations. Analysis of results
imposes the strictest limitations on parameters describing the Hamiltonian,
despite the existing chemical disorder, and thus reveals the critical role
magnetic field can play in illuminating the ground state of QSL candidates,
especially in the presence of disorder.
Steinhardt, WM; Shi, Z; Samarakoon, A; Dissanayake, S; Graf, D; Liu, Y; Zhu, W; Marjerrison, C; Batista, CD; Haravifard, S