Position and Temperature Dependence of Pyroelectricity in Domain-Engineered Stoichiometric and Congruent LiTaO3
John H. Lehman, Chris Pannell
Domain-engineered bicell (parallel compensated) pyroelectric detectors were constructed from stoichiometric and congruent lithium tantalate. The variation of the pyroelectric current response of these detectors was investigated as a function of temperature and position. We define a pyroelectric response gradient Π, which, near boundary of antiparallel domains, is asymmetric and increases to 4 % K-1 in the poled half of the congruent LiTaO3 bicell. The Π variation in the stoichiometric LiTaO3 bicell was also asymmetric and varied only 1 % K-1. The contribution of the primary, secondary, and tertiary pyroelectric effects are discussed along with a summary of the stress and strain in the heated detector disk.