Piezoelectric crystal elements are provided having preferred cut directions that optimize the shear mode piezoelectric properties. In the discovered cut directions, the crystal elements have super-high piezoelectric performance with d15, d24 and d36 shear modes at room temperature. The d15 shear mode crystal gives a maximum d value and is free from the cross-talk of d11 and d16. The d36 mode is extremely reliable compared to other shear elements due to its ready re-poling capability. The crystal elements may be beneficially used for high-sensitive acoustic transducers.
