NONEQUILIBRIUM PHASE-TRANSITION IN KER(MO OS4)(2)

Relaxation absorption of the microwave power in KEr(MoO4)(2) has been measured In the critical region of the structural phase transition of the cooperative Jahn-Teller effect type, which is induced by external magnetic field with varying microwave power. A feature of the relaxati on peak has been revealed, which has a threshold character with respec t to the microwave power pumping. The results obtained are interpreted as it nonequilibrium phase transition induced by microwave field acco mpanied by formation of a coherent structure at phonons.