Modification of pyroelectric crystal TGS using thermodynamic theory

Based on the Devonshire thermodynamic theory, the relationship λ/χ = Ps/C can be regarded as a method to increase the pyroelectric material figure of merit of ferroelectric crystals. Several modified TGS crystals doped with urea or co-doped with urea and other dopants have been grown. The effect of the urea dopant on crystal growth and pyroelectric properties was investigated. The pyroelectric figures of merit M (λ/ε) of the doped TGS crystals are obviously higher than those of pure TGS. Furthermore, the variations of λ/χ and Ps/C as a function of temperature for these doped TGS single crystals were measured, and analyzed according to the Devonshire thermodynamic model.