In a new study published in Light Science & Applications, a team of scientists led by Professor Zhenghua An from Fudan University, Yanru Song from ShanghaiTech University, and co-workers created a superconducting memlogic sensor that combines infrared sensitivity, memory retention, and reconfigurable logic computing, resulting in an all-in-one infrared memlogic sensor.
a, the diagram of LWIR memlogic sensor structure. b, the hysteretic IV curve under light irradiation and without intentional radiation, respectively. c,d, the operation of optical/electrical pulse write/erase data and persist state. e,f, a schematic of the reconfigurable logic circuit and experimental data under different electrical biases. g, high responsivity at the 12.2-micron operating wavelength. Image Credit: AlphaGalileo
Superconducting memlogic sensors combine in-cell logic and memory, taking machine vision beyond traditional computing. These sensors use superconductors’ quantum sensitivity and wide spectrum. We present a long-wave infrared sensor with superconductor-normal phase bistability, which enables deterministic, permanent switching.
Due to metamaterial architecture, this gadget improves encrypted communications and has great infrared sensitivity (12.2 μm). This breakthrough can potentially outperform biological retinas in terms of sensitivity and wavelength, incorporating superior vision into quantum computers.
The number of optical sensors has risen significantly as Artificial Intelligence (AI) and the Internet of Things (IoT) have advanced rapidly. These typical sensors create massive volumes of unstructured and redundant data, resulting in inefficient energy consumption and information delay during data transfer to storage and computation units.
In contrast, the human visual system possesses efficient and low-power parallel processing capabilities, allowing images to be perceived and processed simultaneously.
To overcome the challenges with the von Neumann architecture, researchers created memory-computing systems made of various materials, including 2D, phase-change, and ferroelectrics. However, based on such materials, these systems frequently suffer from poor light sensitivity and significant band gaps, necessitating high-power light sources for optical computing, with few reported capable of in-sensor computation in the long-wave infrared.
AI perception in the infrared domain is important in many applications, including thermal imaging, surveillance, industrial inspection, gas detection, medical thermal imaging, defense, and space exploration.
They show that this superconducting device can be controlled simultaneously in four ways, including optical/electrical biases and optical/electrical pulses, which allow for alternative encoding logic with increasing functional complexity. These reconfigurable procedures demonstrate infrared remote encrypted communication at the single device level.
Given the prevalence of bistable effects, extensive wavelength coverage, and high photo-sensitivity in superconductors, their memlogic sensing concept, which employs superconducting phase transitions, has the potential for versatile applications across a wide electromagnetic spectrum and down to quantum-levels in fields such as machine perception, remote sensing, secure communication, and spatial detection.
“Distinctive from existing superconducting sensors (like SNSPDs and TESs), our device works in the bistable region of the hysteretic superconductor-normal phase transition. This hysteretic IV is often considered as a hindrance to most of the superconducting devices’ performance although they can be indeed utilized as switches or memories. By contrast, here we take the advantages of the hysteresis behavior and show its favorable applications in memlogic optical sensing.”
To overcome the well-known low system detection efficiency of superconducting detection in this long-wave infrared region, we adopt a metamaterial perfect absorber concept which consists of a resonant plasmonic cavity, with tri-layer structure of Nb-Si-Nb,” they added.
“This sensor can be integrated on a large scale and requires only two electrodes for a readout circuit, which is crucial for cryogenic application. Future prospects for this technology include applications in telecommunications, superconducting computing, AI-driven image processing, and intelligent on-chip spectrometers.” the scientists forecasted.
The National Natural Science Foundation of China, the Shanghai Science and Technology Committee, Shanghai Pujiang Program supported the study.
Journal Reference:
Chen, B., et al. (2024) Reconfigurable memlogic long wave infrared sensing with superconductors. Light Science & Applications. doi.org/10.1038/s41377-024-01424-2.