Progress and challenges in blocked impurity band infrared detectors for space-based astronomy

Wang

et al. 2023

Adv Funct Materials

Self Cite

Neuromorphic hardware based on artificial synaptic devices has great potential to break the bottleneck of von Neumann architecture, which makes it possible to emulate the working mode of the human brain with low power consumption and high operation efficiency. However, current synaptic devices can barely detect photons and are bio‐incompatible for future all‐in‐one visual perception technology. Here, synaptic photoconductors based on an organic–inorganic hybrid structure, and composed of photosensitive bacteriorhodopsin protein layer and zinc oxide film are reported. The synaptic photoconductors demonstrate tunable synaptic plasticity with the modulation of the light illumination time and power intensity. The working mechanism of the photogating effect induced by the proton pump process of bR protein molecules is further investigated in detail. Assisting with these properties, the imaging memorization and preprocessing function are successfully emulated by the synaptic photoconductors. The prototype photosynaptic devices provide a unique opportunity to realize artificial synapses, enabling neuromorphic hardware.

Section: Resultsmentioning

confidence: 99%

mentioning

confidence: 99%

Hybrid Bacteriorhodopsin/Zinc Oxide Synaptic Photoconductors for Bio‐compatible Neuromorphic Devices

Wang

et al. 2023

Adv Funct Materials

Self Cite

“…They all have superior IR photoelectric conversion abilities through which one can obtain high-enough quantum efficiency and response. However, because dark current and assisted noise are very sensitive to temperature, most IR photodetectors must operate at a low temperature to improve their signal to noise ratios [ 4 ]. This is understandable, for the energy of circumstance temperature is comparable to a narrow band gap, inducing abundant free carriers and high generation–recombination rates.…”

Section: Introductionmentioning

confidence: 99%

Infrared Photodetection from 2D/3D van der Waals Heterostructures

Tang

Zhong

et al. 2023

Nanomaterials

Self Cite

An infrared photodetector is a critical component that detects, identifies, and tracks complex targets in a detection system. Infrared photodetectors based on 3D bulk materials are widely applied in national defense, military, communications, and astronomy fields. The complex application environment requires higher performance and multi-dimensional capability. The emergence of 2D materials has brought new possibilities to develop next-generation infrared detectors. However, the inherent thickness limitations and the immature preparation of 2D materials still lead to low quantum efficiency and slow response speeds. This review summarizes 2D/3D hybrid van der Waals heterojunctions for infrared photodetection. First, the physical properties of 2D and 3D materials related to detection capability, including thickness, band gap, absorption band, quantum efficiency, and carrier mobility, are summarized. Then, the primary research progress of 2D/3D infrared detectors is reviewed from performance improvement (broadband, high-responsivity, fast response) and new functional devices (two-color detectors, polarization detectors). Importantly, combining low-doped 3D and flexible 2D materials can effectively improve the responsivity and detection speed due to a significant depletion region width. Furthermore, combining the anisotropic 2D lattice structure and high absorbance of 3D materials provides a new strategy in high-performance polarization detectors. This paper offers prospects for developing 2D/3D high-performance infrared detection technology.

“…The blocked-impurity-band (BIB) detector is a new type of THz detector, which uses low-frequency breakthrough technology from infrared to achieve THz detection. With its high sensitivity, large array scale, and wide detection spectrum advantages (Iglesias et al, 2008;Woods et al, 2011), the BIB detector stands out among the THz detectors and has been widely used in space target detection (Reynolds et al, 1989;Werner, 2005), atmospheric monitoring (Hogue et al, 2008), astronomical observation (Hanaoka et al, 2016;Xiao et al, 2022) and other fields (Kaplan et al, 2021;Meng et al, 2022).…”

Section: Introductionmentioning

confidence: 99%

The high-performance linear scan imaging system of terahertz Si-based blocked-impurity-band detector

Tao

Zhang

et al. 2023

Front. Electron. Mater

Terahertz (THz) Si-based blocked-impurity-band (BIB) detector is becoming the overwhelming choice for applications in space-based instruments, airborne, and imaging systems. A high-performance linear scan imaging system based on the THz Si-based BIB detector is designed. Through the optimized design of cryogenic Dewar and a suitable optical system, the imaging system reduces background stray radiation, and then improves the THz imaging performance of the detector. At the temperature of 4.2 K and the bias of 2.6V, the blackbody peak responsivity of the Si-based BIB detector is 23.77A/W, while the dark current is 4.72×10−11 A and the corresponding responsivity non-uniformity is less than 6.8%. Moreover, the experiment results show that the noise equivalent temperature difference (NETD) of the whole system reaches 10mK, and the spatial resolution reaches 50 µm. This work is beneficial to the larger scale array integrated BIB imaging system.