A method for poling barium titanate, BaTiO3

Abstract

Relatively large samples of single crystal barium titanate, BaTiO3, are needed for current photonic applications including for example; optical memories, associative memories and neural networks. The process of producing single-domain crystals called poling usually involves uniaxial pressing to remove orthogonal or 90° domains and then electric field poling to remove antiparallel or 180deg; domains. A method for poling BaTiO3 that significantly reduces the processing time for single-domain sample preparation is described herein. The technique involves the removal, by etching, of surface stresses that mechanically restrict or pin the 90° domains that inhibit their elimination. In this “stress free” state, large volume samples (10 × 10 × 5 mm) are easily electrically poled into single crystals without uniaxial pressing.