Dynamical Symmetry Breaking in Magnetic Systems

The magnetic transition processes with symmetry breaking are studied theoretically on one magnetic moment model and more complex magnetic systems. It is shown that the symmetry-breaking processes behave much more deterministic than could be deduced from energy considerations. The two qualitatively different cases of dynamical control are identified depending on robustness against thermal fluctuations. The first case is robust against thermal fluctuations even if the magnetic transition control parameter is changed adiabatically. The second case is unstable against temperature fluctuations and the result of symmetry breaking is random. If the magnetic transition control parameter is rapidly changed, control over the final magnetic state is regained. This phenomenon is related to precession of magnetic momentum, and therefore, it is not noticeable in methods considering and minimizing energy of the magnetic systems directly.