Abstract
The relaxation dynamics of a uniaxial paramagnet of arbitrary spin value , interacting with a thermal bath, are treated using the spin-boson model for a particular spin Hamiltonian consisting of the simplest uniaxial potential in the high temperature, Ohmic damping, and weak spin-bath coupling limits. The signal-to-noise ratio of the magnetic moment fluctuations in the stochastic resonance of such a paramagnet displays a pronounced dependence on for values of . The dependence arises from the quantum spin dynamics which differs markedly from the magnetization dynamics of classical superparamagnets with .
- Received 20 April 2010
DOI:https://doi.org/10.1103/PhysRevB.81.172411
©2010 American Physical Society