An overview of pyroelectric photodetector: Photoresponse mechanisms and applications

Recently, pyroelectric materials have gained significant interest for energy harvesting, sensing and detection, and so on. For photodetection, pyroelectric photodetectors show great advantages due to high-performance photo-sensing without an external bias voltage. In this review, the pyroelectric coefficients and three types of important figure of merits are introduced. Moreover, the work mechanisms of pyroelectric photodetectors, including light-induced pyroelectric effect, pyroelectric-photoelectric coupled effect, photovoltaic-pyroelectric coupled effect, pyro-phototronic effect, ferro-pyro-phototronic effect, pyro-phototronic and piezo-phototronic coupling effects, and photo-pyroelectric-thermoelectric effect, are systematically summarized. Finally, the survey of the pyroelectric applications for photoresponse is presented, which divided the pyroelectric photoresponse into four major categories consisting ultraviolet detecting, visible detecting, infrared detection, and broadband detection. This review provides a detailed analysis and summarization of the work mechanisms of pyroelectric photodetectors and the photoresponse applications, which will provide significant guidance and inspiration toward designing the improved pyroelectric photodetectors.