Dual-Electrically\nConfigurable MoTe<sub>2</sub>/In<sub>2</sub>S<sub>3</sub> Phototransistor\ntoward Multifunctional Applications

Photodetectors, essential for a wide range of optoelectronic\napplications\nin both military and civilian sectors, face challenges in balancing\nresponsivity, detectivity, and response time due to their inherent\nunidirectional carrier transport mechanism. Multifunctional photodetectors\nthat address these trade-offs are highly sought after for their potential\nto reduce costs, simplify system design, and surpass Moore’s\nLaw limitations. Herein, we present a multimodal phototransistor based\non a 2D MoTe<sub>2</sub>/In<sub>2</sub>S<sub>3</sub> heterostructure.\nThrough dual electrical modulation employing bias voltage and gate\nvoltage, we engineer the energy band to achieve switchable photoresponse\nmechanisms between photoconductive and photovoltaic modes. In photoconductive\nmode, the device exhibits a responsivity of 320 A/W and a specific\ndetectivity of 1.2 × 10<sup>13</sup> Jones. Meanwhile, in photovoltaic\nmode, it exhibits a light on/off ratio of 2 × 10<sup>5</sup> and\nresponse speed of 0.68/0.60 ms. These capabilities enable multifunctional\napplications such as high-resolution imaging across various wavelengths,\na conceptual optoelectronic logic gate, and dual-channel optical communication.\nThis work makes an advancement in the development of future multifunctional\noptoelectronic devices.