Ultra Low Power Consumption Optoelectronic Logic Operation of CuO/BaTiO3 Heterojunction Photodetector with Tunable Internal Electric Field Based on Poling Effect

The study presents a novel self-powered ultraviolet (UV) photodetector harnessing both polarization fields and photovoltaic effects, enabling the realization of ultra-low power, reconfigurable optoelectronic logic gates. The approach is demonstrated on a CuO/BaTiO₃ heterojunction photodetector. The behavior of the photodetector is augmented by the poling effect, aligning the internal electric field of the BaTiO₃ through the application of a robust external electric field, thereby facilitating the implementation of optoelectronic logic gates. In the unpoled state, the “XOR” and “OR” logic gates operated at voltages of 750 and −500 µV, respectively. However, upon poling up state, the “XOR” logic gate exhibits reduced operation voltage, operating at 500 µV, while the “OR” logic gate implements clarity at −500 µV. In the unpoled state the “AND” logic gate does not operate; however, upon poling in the downward direction, it operated at −500 µV. The achievement demonstrates successful ultra-low-power logic operations, utilizing voltages in the hundreds of micron scale, under a 310 nm wavelength and a light intensity of 0.52 mW·cm⁻². Furthermore, controllable polarization electric fields in BaTiO₃ enable the operation of “AND” logic gate in the unpoled state, presenting a promising avenue for future research in optoelectronic logic gate design.