Surface acoustic wave propagation properties in 0.67Pb(Mg1/3Nb2/3)O3-0.33PbTiO3 single crystal poled along [111]c

Surface acoustic wave (SAW) propagation properties in relaxor-based 0.67Pb(Mg1/3Nb2/3)O3-0.33PbTiO3 (PMN-33%PT) ferroelectric single crystals poled along [111]c has been analyzed theoretically. We found that the X-cut PMN-33%PT has lower phase velocity and higher electromechanical coupling coefficient compared to traditional piezoelectric materials. The power flow angle (PFA) can be zero in specific directions, which could drastically improve the performance of SAW devices. Our theoretical results indicate that the direction about 5° canted from [111]c is the optimum direction for the X-cut [111]c poled crystals in SAW device applications. Characteristic curves were also obtained for the phase velocity, electromechanical coupling coefficient, and PFA in Z-cut single-domain PMN-33%PT single crystals.