Random anisotropy magnet at finite temperature

Abstract

We present finite-temperature Monte Carlo studies of a 2D random-anisotropy (RA) magnet on lattices containing one million spins. The correlated spin-glass state predicted by analytical theories is reproduced in simulations, as are the field-cooled and zero-field-cooled magnetization curves observed in experiments. The orientations of lattice spins begin to freeze when the temperature is lowered. The freezing transition is due to the energy barriers generated by the RA rather than due to random interactions in conventional spin-glasses. We describe freezing by introducing the time-dependent spin-glass order parameter q and the spin-melting time τ M defined via q = τ M/t above freezing, where t is the time of the experiment represented by the number of Monte Carlo steps.

Document Details

Document Type
Pub Defense Publication
Publication Date
May 11, 2022
Source ID
10.1088/1361-648x/ac684a

Entities

People

  • D. A. Garanin
  • Eugene Chudnovsky

Organizations

  • Air Force Office of Scientific Research

Tags

Fields of Study

  • Physics

Readers

  • Computational Modeling and Simulation
  • Materials Science and Engineering.
  • Superconducting Magnet Technology