Realization of the kagome spin ice state in a frustrated intermetallic compound

Abstract

Looking for a crystalline 2D spin ice Spin ices—materials in which local magnetic spins respect “ice rules” similar to those in water ice—are typically three-dimensional. Two-dimensional (2D) ice rules can also be formulated and have been found to be satisfied in engineered nanomagnetic systems, usually referred to as artificial spin ices. Zhao et al. used neutron scattering and thermodynamic measurements to study a crystalline candidate for a 2D spin ice, the intermetallic compound HoAgGe. They found that at low temperatures, the local spins on the distorted kagome planes of this quasi-2D material respect 2D ice rules. Increasing the temperature led to a series of transitions consistent with theoretical expectations. Science , this issue p. 1218