Investigations on Scattering Centers in CsB3O5 Crystals

Cesium triborate (CsB3O5: CBO) crystal is an important nonlinear optical crystal for UV light generation. Although the crystals contain scattering centers, postgrowth quenching of the crystals is successful in reducing the scattering centers. After in-depth experimental analysis of the quenching process we propose the existence of retrograde solid solution region at high temperatures in CBO. Based on the retrograde solid solution curve we are able to reduce the scattering centers in CBO crystals by the vapor transport equilibration process. By our hypothesis we are able to explain the experimental results and mechanism of formation of scattering centers in CBO crystals.