Infrared absorbing oxide electrodes in epitaxial pyroelectric Pb-La-Ti-O heterostructures with controlled domain orientation

Abstract Oxide-based pyroelectric heterostructures of La-Sr-Co-O/ Pb0.9La0.1Ti0.975O3/La-Sr-Co-O have been grown. Single-crystal LaAlO3substrates were chosen to obtain high quality epitaxial thin films in order to address basic pyroelectric properties. The use of perovskite conducting oxide electrodes promotes the formation of phase pure perovskite pyroelectric material. Additionally, these oxides exhibit strong infrared absorption, α = 105/cm. An infrared absorbing electrode is beneficial for producing a simplified detector design with enhanced detectivity. Variation of the deposition temperature produced control of the domain orientation. Pyroelectric measurements using the Byer-Roundy method have yielded pyroelectric coefficients of 50 nC/cm2K. Both pyroelectric coefficients and pulsed polarization values show a clear dependence on the c-axis volume fraction.

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