Phase conjugation in fibre-like BTO crystals with applied electric ac field

Self-pumped and mutually pumped phase conjugation based on the fanning effect is demonstrated in photorefractive Bi12TiO20 (BTO) crystals with applied electric ac fields. We used fibre-like crystals that enable a long interaction region and high applied electric fields. We realized three types of phase conjugate mirrors: internally self-pumped, externally self-pumped and mutually pumped. Experimental results characterizing the spatial and temporal behaviour of the phase conjugated wave, the reflection of intensity and phase patterns, and the quality of the phase conjugation are presented.