THERMAL EXPANSIONS OF PURE AND AL-DOPED CSLIB6O10 CRYSTALS FOR NONLINEAR-OPTICAL APPLICATIONS

Changes in X-ray powder diffraction patterns of pure and Al-doped CSLi B6O10 (CLBO) crystals for nonlinear optics upon heating are observed b etween room temperature and 500 degrees C. The crystals undergo linear elongation by about 2x10(-5) deg(-1) along the a-axis, and contractio n by about -2x10(-5) deg(-5) is observed along the c-axis. Such extrao rdinary behavior on heating is a reflection of the structure of CLBO w hich costists mainly of a combination of hexagonal B3O4 rings, and a m arked difference in linkage of the rings appears between een the a- an d c-axes. No significant changes in the thermal expansion coefficients are observed on Al-doping, though considerable expansions along the a - and c-axis are observed.