Lateral-field temperature behavior of lithium tetraborate

Lithium tetraborate (LBO) is a tetragonal material exhibiting piezoelectric coupling values that fall between those of lithium niobate and quartz, with double rotated orientations of zero temperature coefficient (TC) for both bulk and surface wave modes. The authors present calculations for double rotated resonators and compute the coupling factors for the three simple thickness modes driven by lateral quasistatic electric fields as a function of the orientation angles and the direction of the applied lateral field. Double rotate thickness-mode plate resonators of LBO driven in [LE] are found to have loci of zero TC of frequency first and second order, for all three modes. Orientations are found where the first and second TC values are low, simultaneously, and where the associate dpiezocoupling is moderately large