Position and temperature dependence of pyroelectricity in domain-engineered stoichiometric and congruent LiTaO3

Domain-engineered bicell (parallel compensated) pyroclectric 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 Pi, which, near boundary of antiparallel domains, is asymmetric and increases to 4% K-1 in the poled half of the congruent LiTaO3 bicell. The Pi 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.