Electro-elastic properties of YCa₄O(BO₃)₃ piezoelectric crystals

YCa₄O(BO₃)₃ (YCOB) crystal was reported to be a potential material for high temperature piezoelectric sensing applications. In this paper, the full matrix of electro-elastic constants, including dielectric permittivities, elastic constants, and piezoelectric coefficients were determined. The relative dielectric permittivities were measured to be ε₁₁^T/ε₀=9.65, ε₂₂^T/ε₀=11.80, ε ₃₃^T/ε₀=9.55, and ε₁₃ ^T/ε₀=0.95, respectively. The piezoelectric coefficients were determined to be d₁₁ = 1.7, d₁₂ = 3.9, d₁₃ = -4.2, d₁₅ = -1.1, d₂₄ = 4.4, d ₂₆ = 7.9, d₃₁ = -0.77, d₃₂ = -2.5, d ₃₃ = 1.4, and d₃₅ = -5.0 pC N^-1. In addition, piezoelectric cross-talks of YCOB crystals were investigated, where (XZlw)45°/35° and (YXt)-30° crystal cuts were found to possess pure thickness shear mode, with relatively large effective piezoelectric coefficients, being on the order of d₁₅ = 8.8 and d₂₆ = 9.0 pC N^-1, respectively.