Enhancing Photocurrent of Radially Polarized Ferroelectric BaTiO3 Materials by Ferro-Pyro-Phototronic Effect

The pyro-phototronic effect has been utilized to modulate photoexcited carriers, to enhance the photocurrent in semiconducting nanomaterials. However, most of these materials have low pyroelectric performances. Using radially polarized ferroelectric BaTiO3 materials with a pyroelectric coefficient of about 16 nC/cm2K, we report a dramatic photocurrent enhancement due to ferro-pyro-phototronic effect. The fabricated device enables a fast sensing of 365-nm light illumination with a response time of 0.5 s at the rising edge, where the output current-time curve displays a sharp peak followed by a stable plateau. By applying a heating temperature variation, the output current peak can be enhanced by more than 30 times under a light intensity of 0.6 mW/cm2. Moreover, the stable current plateau can be enhanced by 23% after utilizing a cooling temperature variation, which can be well explained by ferro-pyro-phototronic-effect-induced energy band bending.