Emerging Single‐Photon Detectors Based on Low‐Dimensional Materials

Abstract

Single‐photon detectors (SPDs) that can sense individual photons are the most sensitive instruments for photodetection. Established SPDs such as conventional silicon or III–V compound semiconductor avalanche diodes and photomultiplier tubes have been used in a wide range of time‐correlated photon‐counting applications, including quantum information technologies, in vivo biomedical imaging, time‐of‐flight 3D scanners, and deep‐space optical communications. However, further development of these fields requires more sophisticated detectors with high detection efficiency, fast response, and photon‐number‐resolving ability, etc. Thereby, significant efforts have been made to improve the performance of conventional SPDs and to develop new photon‐counting technologies. In this review, the working mechanisms and key performance metrics of conventional SPDs are first summarized. Then emerging photon‐counting detectors (in the visible to infrared range) based on 0D quantum dots, 1D quantum nanowires, and 2D layered materials are discussed. These low‐dimensional materials exhibit many exotic properties due to the quantum confinement effect. And photodetectors built from these nD‐materials (n = 0, 1, 2) can potentially be used for ultra‐weak light detection. By reviewing the status and discussing the challenges faced by SPDs, this review aims to provide future perspectives on the research directions of emerging photon‐counting technologies.

Nanomaterials for Quantum Information Science and Engineering

“…Electron-hole pairs (EHPs) created by a single incident photon in the depletion region experience a large electric field, causing them to accelerate and generate additional carriers, which then further excite more carriers. However, SPADs have detection efficiencies well below unity, high timing jitter, and high dark count rates [559][560][561] . Superconducting SPDs are another general class of detectors that generally exhibit high efficiency at telecom wavelengths and low timing jitter [562] .…”

“…As discussed in section 4, various 2D materials have been shown to exhibit superconductivity or to be high-performance weak-link layers in a JJ. Atomically thin superconductors will have a lower heat capacity than the bulk and therefore could be more sensitive to single photons [561] . Recently, Walsh et al utilized the localized surface plasmon modes of graphene to couple light to a graphene-based JJ [574] .…”

“…However, this device still suffers from high timing jitter. QD devices, in general, possess excellent sensitivity but struggle with timing jitter and must be operated at cryogenic temperatures to have low dark counts [561] .…”

Silicon photonic devices for scalable quantum information applications

“…More details about integrated singlephoton detectors are summarized in Table II. In addition to these conventional devices, single-photon detection based on low-dimensional materials is emerging and has shown superior performance [101].…”

Engineering sensitivity and spectral range of photodetection in van der Waals materials and hybrids

“…Low noise and efficient photogating effect of the hybrid leads to the unique ability for this heterostructure to perform number-resolved photodetection. Conventional single photon detectors like Si avalanche photodiodes, superconducting nanowires etc, which are commercially available, suffer from drawbacks such as single-noise ratio, spectral operational range and photon-number resolving ability and with high demand in the emerging quantum technology field, there is ample room for improvement [174,175]. Carrier multiplication through avalanche breakdown is a well-established process to increase the internal gain of a photodetector.…”