Local charge formation in LiNbO3 using a mobile needle-shaped electrode

It is shown that local formation of electric charge in a region near the su rface of lithium niobate crystals can take place both by local polarization switching of the sample and by local injection of electric charge from a n eedle-shaped electrode. A local change, due to the electrooptic effect, in the birefringence of the sample near the charged region is used to investig ate the nature and the formation mechanism of the charge relief. (C) 1999 A merican Institute of Physics. [S1063-7834(99)02703-3].