Parity Effect in the Resonant Tunneling

A mechanism of the parity effect in the thermally assisted resonant tunneling is proposed in the view point of nonadiabatic transitions of thermally excited states. In this mechanism, alternating enhancement of the relaxation is naturally understood as a general property of quantum relaxation of uniaxial magnets at finite temperatures where appreciable populations are pumped up to excited states. It is also found that the enhanced sequence depends on the sweeping rate of the field.