Versatile near-infrared polarization-sensitive ionic liquid-gated organic electrochemical phototransistor†

In response to the rising demand for diversified detection capabilities, multi-dimensional and multi-functional optoelectronic devices have become a significant focus in scientific research. The organic electrochemical phototransistor (OECPT) is a pioneering photoelectric conversion device whose unique operating mechanism positions it as a strong candidate for applications in areas such as biological systems, sensing, and artificial neural network modeling. In this study, polarization-responsive OECPT devices were fabricated by combining thermally oriented anisotropic thin films with ionic liquid gating. The resulting devices demonstrated a distinct polarization sensitivity in the near-infrared region, achieving a photogenerated current dichroic ratio of 1.52. Furthermore, by modulating device non-volatility vis gate voltage, we explored the potential of OECPTs in neural synapse emulation and optoelectronic memory storage. These findings provide valuable insights for advancing the design and application of polarization-sensitive OECPT devices in multifunctional optoelectronic systems.