title: Frustrated quantum critical theory of putative spin-liquid phenomenology in 6H-B-Ba(3)NiSb(2)O(9).
abstract: A recently discovered material, 6H-B-Ba(3)NiSb(2)O(9) was found to display unusual low-temperature phenomenology, interpreted as a quantum spin liquid with spin S=1 on a triangular lattice. We study a spin S=1 exchange model on an AB stacked triangular lattice near its quantum paramagnet-to-spiral transition, driven by easy-plane single-ion anisotropy. We demonstrate that the frustrated inter- and intralayer exchanges induce contour lines of low-energy excitations that lead to a broad crossover regime of linear-temperature dependence of the specific heat. Based on this and various other predictions, we argue that the observed phenomenology can be understood in terms of a conventional picture of a proximity to this frustrated critical point.
authors.affiliation: Department of Physics, University of Colorado, Boulder, Colorado 80309, USA.
authors.forename: G
authors.initials: G
authors.lastname: Chen
authors.forename: M
authors.initials: M
authors.lastname: Hermele
authors.forename: L
authors.initials: L
authors.lastname: Radzihovsky