Ferroelectric Tunable Nonvolatile Polarization Detection Based on 2H α-In₂Se₃

The development of polarization photodetectors utilizing two-dimensional materials holds significant promise due to their distinctive properties and potential for high integration. However, a major limitation of most current polarization photodetectors is their lack of polarization tuning capability, which restricts the versatility of individual devices. In this study, a nonvolatile ferroelectric tunable polarization photodetector is explored based on 2H α-In₂Se₃. The ferroelectric semiconductor field-effect transistor (FeS-FET) based on 2H α-In₂Se₃ were fabricated, demonstrating an on/off ratio of 10³. Ferroelectric modulation photoelectric response was explored under 650 nm illumination, the device achieves a maximum optical responsivity of 75 A/W, with a detectivity of 1.46 × 10¹⁰ jones. Notably, in the context of polarized light detection, the device's polarization sensitivity experiences significant modulation due to ferroelectric polarization switching. The dichroic ratios can be tuned to 1.74 and 3 for polarization down and up states, respectively. Moreover, by adjusting the degree of ferroelectric polarization switching, the dichroic ratio can be linearly tuned. The polarization up state can continuously enhance the dichroic ratio in the range of 2.71-3.11, while the polarization down state can continuously weaken the dichroic ratio in the range of 2.54-2.06. This research not only advances the understanding of 2H α-In₂Se₃ in polarization detection but also introduces a nonvolatile ferroelectric modulation approach for tunable polarization detection.