Spectroscopic and photorefractive properties of infrared-sensitive rhodium-doped barium titanate

Abstract

We have grown and characterized crystals of BaTiO(3) doped with Rh. These crystals have a blue-green color that is probably due to charge-transfer optical transitions involving Rh(4+) and/or Rh(3+). Electron paramagnetic resonance spectroscopy confirmed the presence of Rh(4+) centers. Self-pumped phase-conjugation measurements were performed at wavelengths between 776 and 990 nm. Reflectivities near 80% were obtained throughout this wavelength range. In addition, self-pumped phase-conjugation buildup times were measured as a function of input power at 851 nm and are significantly faster than in undoped or Co-doped crystals studied previously. BaTiO(3):Rh is therefore a promising material for near-infrared photorefractive applications.