• • The LSMO/BLFO/Q2DEG heterostructure exhibits a persistent photoconductivity that increases with illumination duration, reaching a maximum photocurrent of approximately 1.2 mA after 5 minutes of illumination under open/open conditions, compared to 0.8 mA for the Pt/BLFO/Q2DEG device. This 50% enhancement is critical for non-volatile memory applications, where higher on/off ratios enable reliable data retention and lower read errors.
• • Dark waiting after 5 minutes of illumination results in a gradual decay of photocurrent, with the LSMO device retaining 70% of its initial photocurrent after 30 minutes in the dark, while the Pt device retains only 40%. This retention difference underscores the role of the LSMO electrode in stabilizing charge trapping, which is essential for long-term data storage in oxide photoelectric memories.
• • The I-V curves measured under closed/closed, closed/open, and open/open conditions reveal that the electrical connection between the top electrode and the Q2DEG during illumination and dark waiting significantly modulates the photoresponse. The open/open configuration yields the highest photocurrent, suggesting that disconnecting the electrodes prevents charge recombination and enhances charge separation, a key operational threshold for device design.
• • The observed chargeable photoconductivity is attributed to the ferroelectric polarization of BLFO and the high-mobility Q2DEG, which together facilitate efficient charge separation and trapping. The LSMO/BLFO/Q2DEG heterostructure demonstrates a photoresponsivity of 2.5 A/W at 1 V bias, surpassing many conventional oxide photodetectors, and offers a viable route for integrating multiferroic materials into next-generation optoelectronic memory arrays.