Magnetic ordering and slow dynamics of frustrated systems

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Magnetic ordering and slow dynamics of frustrated magnets have been studied theoretically and numerically mainly for spin glasses. Particular attention was paid to the "chirality", a quantity of recent theoretical and experimental interest. We examined whether the peculiar behavior of the "spin-chirality decoupling" proposed recently really occurred or not, as well as various off-equilibrium phenomena induced by the chirality such as the violation of the fluctuation-dissipation relation. We performed a large scale Monte Carlo simulation of the 3D Heisenberg Edward-Anderson model, and have revealed the existence of a finite-temperature chiral-glass transition and of the spin-chirality decoupling phenomenon at long length and time scales, as predicted by the present author. It was also found that the peculiar one-step-like replica-symmetry breaking (RSB) occurred in the chiral-glass ordered state. In magnetic fields, this RSB gives rise to a thermodynamic SQ transition even in fields, which consistently explains the long-standing experimental puzzle for the in-field behavior of canonical spin glasses. The peculiar RSB pattern was indeed observed by means of off-equilibrium simulations of spin glasses via the violation of the fluctuation-dissipation theorem.