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Mainstream non‐volatile memory (NVM) devices based on floating gate structures or phase‐change/ferroelectric materials face inherent limitations that compromise their suitability for long‐term data storage. To address this challenge, a novel memory device based on light‐programmed lattice engineering of thin rhenium disulfide (ReS2 ) flakes is proposed. By inducing sulfur vacancies in the ReS2 channel through light illumination, the device's electrical conductivity is modified accordingly and multiple conductance states for data storage therefore are generated. The device exhibits more than 128 distinct states with linearly increasing conductance, corresponding to a sevenfold increase in storage density. Through further optimization to achieve atomic‐level precision in defect creation, it is possible to achieve even higher storage densities. These states are extremely stable in vacuum or inert ambient showing long retention of >10 years, while they can be erased upon exposure to the air. The ReS2 memory device can maintain its stability over multiple program‐erase operation cycles and shows superior wavelength discrimination capability for incident light in the range of 405–785 nm. This device represents a significant contribution to NVM technology by offering the ability to store information in multistate memory and enabling filter‐free color image recorder applications.

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Artificial photoreceptors offer a promising solution for developing biomimetic vision systems that incorporate in‐sensor processing, which can greatly reduce power consumption and operation latency compared to traditional machine vision systems. This work presents a tetrachromatic optical synaptic device based on a 2D tungsten diselenide optoelectronic p‐type transistor with a unique UV light‐activated surface electron doping layer. Fully light‐controlled bidirectional synaptic excitation and inhibition are demonstrated with visible and UV light stimuli, respectively, with a reasonable power density of <10 mW cm−2 that matches the imaging condition of a biological vision. The weight updates of up to 64 states, high dynamic range, and low nonlinearity are demonstrated for long‐term potentiation and depression behaviors. This artificial tetrachromatic photoreceptor can mimic the alert and foraging behaviors of a reindeer with low power consumption and enhanced signal contrast. Furthermore, it can be employed as an intelligent collision detection solution with in‐sensor processing capabilities. This bioinspired tetrachromatic photoreceptor offers a low‐cost, energy‐efficient, and low‐latency solution for future artificial machines.

Two‐dimensional semiconductors are considered as promising candidates in next‐generation nanoelectronics. The polarity regulation, however, has been a great obstacle to their applications. Herein, a strategy to comprehensively modulate the polarity of WSe2 field‐effect transistors (FETs) by combining contact engineering and plasma doping is demonstrated. N‐type and ambipolar WSe2 FETs are obtained by indium (In) and chromium (Cr) contact, respectively. Meanwhile Cr contact and mild oxygen plasma doping are employed simultaneously to realize p‐type WSe2 FET. High on/off ratio of ≈107 has been achieved for both n‐type and p‐type WSe2 FETs. Subsequently, they are connected in series to construct a homogeneous complementary logic inverter and a lateral p–n diode. Anti‐ambipolar transfer characteristics, therefore, are accessed from the inverter. And the forward to backward rectifying ratio reaches 106 for the p–n diode. The proposed strategy paves the way for practical applications of WSe2 FETs in logic circuits and optoelectronics.