Single-domain electromechanical constants for Pb(Zn1/3Nb2/3)O3-4.5%PbTiO3 from micro-Brillouin scattering -: art. no. 042908

We report a complete set of elastic and piezoelectric constants for single-domain rhombohedral Pb(Zn(1/3)Nb(2/3))O(3)-4.5%PbTiO(3), poled in the < 111 > direction using micro-Brillouin scattering. We find the bulk modulus and elastic constants to agree with the values obtained from ultrasonic and resonance methods, but obtain smaller piezoelectric constants. Brillouin spectroscopy probes microregions of the crystal at high frequencies. The differences in material constants obtained by acoustic measurements on multidomain samples and Brillouin measurements of single domains are due to frequency dependence of the piezoelectric constants, and/or point to extrinsic contributions of domain boundaries to the electromechanical response in single-crystal relaxor ferroelectrics.