Cryogenic transverse and shear mode properties of (1 − x)Pb(Mg1/3Nb2/3)O3–xPbTiO3 single crystal with the optimal crystallographic direction

The cryogenic transverse extensional and thickness shear properties of the (1 − x)Pb(Mg1/3Nb2/3)O3–xPbTiO3 (PMN–xPT) single crystal with the optimal crystallographic directions were investigated in present work. With the temperature down to 78 K, a characteristic decrease in piezoelectric strain constants (d31, 2020–831 pC N−1 and d15, 4114–2823 pC N−1) and compliance coefficients (image, 95.3–50.6 × 10−12 m2 N−1 and image, 227–184 × 10−12 m2 N−1) was demonstrated. In comparison, the piezoelectric voltage constant (g31 and g15) and electromechanical coupling coefficient (k31 and k15) exhibits an almost temperature-independent behavior. Even at 78 K, high values of g31 ∼ 0.045 Vm N−1, g15 ∼ 0.057 Vm N−1, k31 ∼ 0.86, and k15 ∼ 0.94 can be obtained. Such superior low temperature piezoelectric performance is favorable for the cryogenic device designs and applications, especially for the hydrophones with high gij needed.