FERROELECTRIC CRYSTAL ELEMENT AND SECOND HARMONIC GENERATING ELEMENT FORMED BY USING THE SAME

摘要

PURPOSE:To obtain the ferroelectric crystal element which can easily form a polarization inversion structure of a high resolving Power with good accuracy without using a intricate process for a crystal having an arbitrary shape by depositing a thin film of a doping element on a dielectric crystal by using a laser deposition method and subjecting the film to a heat treatment. CONSTITUTION:An LN single crystal fiber 7 is irradiated with a laser beam from a KrF excimer laser 1 via an objective lens 3 of a UV microscope 2 of a laser deposition device. TiCl4 is used as a reactive gas for imparting the doping element Ti and the LN single crystal fiber 7 is irradiated with 200 pulses of the laser beam of 3nJ/pulse energy by directing the +C axis of the fiber upward (laser beam side) and thereafter, a precision X-stage 9 is moved by 12mum and the fiber is again irradiated with 200 pulses of the laser beam. The above-mentioned operations are repeated. Consequently, the L fiber 7 deposited at 6mum width in the +C direction at 12mum interval is obtd. This LN fiber 7 is heat treated for 5 hours at 1050 deg.C, by which the ferroelectric crystal element of the polarization inversion structure having 12mum period is obtd.