No abstract

No abstract

Photorefractive wave mixing in a waveguide geometry with nonguided external pumps has been studied experimentally and theoretically. Guided beam amplification has been obtained in an iron-doped lithium niobate waveguide. Additionally, photorefractive grating couplers that allow the transverse profile of the decoupled guided beam to be controlled are demonstrated.

Photorefractive wave mixing in a waveguide geometry has been demonstrated recently in experiments with such materials as LiNbO3,1 or BaTiO3.2 The high photorefractive efficiency of the latter material allowed even the self-phase conjugation process using guided beams to be observed.2 The waveguide geometry often leads to significant improvement of the photorefractive response time due to the high light intensity caused by spatial confinement. It also offers the possibility of performing wave mixing directly in integrated optics devices. Additionally, very promising photorefractive polymers favor the thin film geometry due to the need for electric poling.3

No abstract