Continuous magnetic phase transition in artificial square ice
arXiv:1905.07246 · doi:10.1103/PhysRevB.99.214430
Abstract
Critical behavior is very common in many fields of science and a wide variety of many-body systems exhibit emergent critical phenomena. The beauty of critical phase transitions lies in their scale-free properties, such that the temperature dependence of physical parameters of systems differing at the microscopic scale can be described by the same generic power laws. In this work we establish the critical properties of the antiferromagnetic phase transition in artificial square ice, showing that it belongs to the two-dimensional Ising universality class, which extends the applicability of such concepts from atomistic to mesoscopic magnets. Combining soft x-ray resonant magnetic scattering experiments and Monte Carlo simulations, we characterize the transition to the low temperature long range order expected for the artificial square ice system. By measuring the critical scattering, we provide direct quantitative evidence of a continuous magnetic phase transition, obtaining critical exponents which are compatible with those of the two-dimensional Ising universality class. In addition, by varying the blocking temperature relative to the phase transition temperature, we demonstrate its influence on the out-of-equilibrium dynamics due to critical slowing down at the phase transition.
References in corpus (9)
- Artificial "spin ice" in a geometrically frustrated lattice of nanoscale ferromagnetic islands
- Direct observation of the ice rule in artificial kagome spin ice
- Extensive degeneracy, Coulomb phase and magnetic monopoles in an artificial realization of the square ice model
- Artificial square ice and related dipolar nanoarrays
- Pinch Points and Kasteleyn Transitions: How Spin Ice Changes its Entropy
- Kagomé ice state in the dipolar spin ice Dy_{2}Ti_{2}O_{7}
- Exploring the Kibble-Zurek mechanism with homogeneous Bose gases
- Magnetic diffuse scattering in artificial kagome spin ice
- Static properties of 2D spin-ice as a sixteen-vertex model