Vibrational resonance in narrow-band conductors

The response is studied of a narrow-band conductor with bcc lattice to a low-frequency signal under presence of a high-frequency signal. In a high enough dc electric field Ex, the conduction electrons form a bistable system, which results in spontaneous appearance of a transverse electric field Ey. Ac field along y axis leads to amplification of the low-frequency signal with non-monotonous dependence of the gain on the high-frequency field amplitude, so that vibrational resonance takes place. Besides, high-frequency field induced nonequilibrium phase transition is found.