DIELECTRIC-PROPERTIES OF BETA-BARIUM BORATE AND POTASSIUM PENTABORATESINGLE-CRYSTALS

Single crystals of beta barium borate and potassium pentaborate (commo nly known as beta-BaB2O4 or BBO and KB5O8. 4 H2O or KB5) were grown by high and low temperature solution growth methods, respectively. The d ielectric constant and loss tangent were determined as a function of t emperature. Frequency response of the dielectric constant and tan delt a have been studied over a frequency range of 0.1 - 100 kHz; it is fou nd that both the dielectric constant and tan delta decrease with incre ase in frequency for both crystals. The dielectric constant and tan de lta are found to increase with increase in temperature for both the cr ystals. Further, the dielectric constant and tan delta measured on dif ferent orientations of the grown crystals reveal the anisotropic natur e of the crystals.