Meta-optical and thin film devices for all-optical information processing

Abstract

All-optical spatial frequency filtering has a long history with many applications now commonly replaced with digital alternatives. Although optical approaches are attractive in that they minimize energy requirements and images can be manipulated in real time, they are relatively bulky compared to the compact electronic devices that are now ubiquitous. With emerging interest in nanophotonic approaches to all-optical information processing, these approaches to enhancing images and performing phase visualization are attracting significant interest. Metasurfaces have been demonstrated as tailored alternatives to conventional spatial filters, but utilizing the spatial frequency sensitivity of these and thin film devices also has the potential to form the basis for ultracompact approaches to image processing. There are, however, significant challenges remaining to realize this promise. This review summarizes the current status of research in this rapidly growing field, places it in the context of the history of all-optical spatial filtering, and assesses prospects for future directions.

Artificial Intelligence in Meta-optics

“…The great advantages of meta-devices are their new properties, compact size, lighter weight, high efficiency, better performance, broadband operation, lower energy consumption, data volume reduction, and CMOS compatibility for mass production. Optical meta-devices have been well-developed for beam shaping, , anomalous deflection and reflection, ,, polarization control and analysis, − holographic images, − nonlinear effects, ,− lasing, , tunability, − color display, − light focusing, − imaging, ,,− image processing, beam shaping, multiplex color routing, sensing, ,− encryption, , spectrometry, optical characterization, , communication, , augmented reality, , and quantum technology. , …”

“…For AI technology, converting the deep learning neural network based on a programming language into an optical neural network can increase the computing speed from the speed of electrons to the speed of photons. Meta-optics for all-optical information processing have already been noticed . In this section, we introduce several functional meta-devices that have the potential to be used in the development of optical neural networks or optical computation.…”

“…Meta-optics for all-optical information processing have already been noticed. 75 In this section, we introduce several functional meta-devices that have the potential to be used in the development of optical neural networks or optical computation. The potential meta-devices for optical computation are categorized into wavefront engineering, nonlinear operation, and edge detection.…”

Computation at the speed of light: metamaterials for all-optical calculations and neural networks

“…Research into photonic devices for all-optical computations has been fruitful over the past few decades 5 – 12 All-optical analog computing opens the door for large real-time parallel computations with minimal energy requirements, which in the energy-conscious reality that we live in with such massive reliance on big data calculations, practical realizations of low-energy real-time image, and data processing could be fundamental to unlocking the next generation of all-optical, or optoelectronic devices. Rather than using the standard “0” and “1” bits used for digital calculations and postprocessing of data, electromagnetic (EM) fields can be exploited to perform calculations and operations optically at the speed of light.…”

Computing metasurfaces enabled chiral edge image sensing

“…Computing metasurfaces are two-dimensional artificial nanostructures capable of performing mathematical operations on the input electromagnetic field ( Silva et al., 2014 ; Pors et al., 2015 ; Hwang and Davis, 2016 ; Zhu et al., 2017 ; Lee et al., 2017 ; Zangeneh-Nejad et al., 2020 ; Li et al., 2021 ; Jin et al., 2021 ; Yung et al., 2022 ; He et al., 2022 ; Fu et al., 2022 ). The spatial differentiation operations based on computing metasurfaces have been applied for all-optical image processing, especially for edge detection ( Dong et al., 2018 ; Kwon et al., 2018 ; Zhou et al., 2019 , 2020 , 2021 ; Momeni et al., 2019 ; Huo et al., 2020 ; Liu et al., 2020 ; Wesemann et al., 2021 ; Solntsev et al., 2021 ; Yang et al., 2021 ). In recent years, because of the sensitivity to changes in physical parameters of the system, weak-value amplification techniques have been proposed for the chiral sensing ( Rhee et al., 2013 ; Wang et al., 2020 ).…”