skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.


Title: Physics-informed machine learning for inverse design of optical metamaterials
Optical metasurfaces consist of densely arranged unit cells that manipulate light through various light confinement and scattering processes. Due to its unique advantages, such as high performance, small form factor and easy integration with semiconductor devices, metasurfaces have been gathering increasing attention in fields such as displays, imaging, sensing and optical computation. Despite advances in fabrication and characterization, a viable design prediction for suitable optical response remains challenging for complex optical metamaterial systems. The computation cost required to obtain the optimal design exponentially grows as the design complexity increases. Furthermore, the design prediction is challenging since the inverse problem is often ill-posed. In recent years, deep learning (DL) methods have shown great promise in the area of inverse design. Inspired by this and the capability of DL to produce fast inference, we introduce a physics-informed DL framework to expedite the computation for the inverse design of metasurfaces. Addition of the physics-based constraints improve generalizability of the DL model while reducing data burden. Our approach introduces a tandem DL architecture with physics-based learning to alleviate the nonuniqueness issue by selecting designs that are scientifically consistent, with low error in design prediction and accurate reconstruction of optical responses. To prove the concept, we focus on the inverse design of a representative plasmonic device that consists of metal gratings deposited on a dielectric film on top of a metal substrate. The optical response of the device is determined by the geometrical dimensions as well as the material properties. The training and testing data are obtained through Rigorous Coupled-Wave Analysis (RCWA), while the physics-based constraint is derived from solving the electromagnetic (EM) wave equations for a simplified homogenized model. We consider the prediction of design for the optical response of a single wavelength incident or a spectrum of wavelength in the visible light range. Our model converges with an accuracy up to 97% for inverse design prediction with the optical response for the visible light spectrum as input. The model is also able to predict design with accuracy up to 96% and optical response reconstruction accuracy of 99% for optical response of a single wavelength of light as input.  more » « less
Award ID(s):
1921857 2108784
PAR ID:
10468058
Author(s) / Creator(s):
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Advanced Photonics Research
ISSN:
2699-9293
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. Optical metamaterials manipulate light through various confinement and scattering processes, offering unique advantages like high performance, small form factor and easy integration with semiconductor devices. However, designing metasurfaces with suitable optical responses for complex metamaterial systems remains challenging due to the exponentially growing computation cost and the ill‐posed nature of inverse problems. To expedite the computation for the inverse design of metasurfaces, a physics‐informed deep learning (DL) framework is used. A tandem DL architecture with physics‐based learning is used to select designs that are scientifically consistent, have low error in design prediction, and accurate reconstruction of optical responses. The authors focus on the inverse design of a representative plasmonic device and consider the prediction of design for the optical response of a single wavelength incident or a spectrum of wavelength in the visible light range. The physics‐based constraint is derived from solving the electromagnetic wave equations for a simplified homogenized model. The model converges with an accuracy up to 97% for inverse design prediction with the optical response for the visible light spectrum as input, and up to 96% for optical response of single wavelength of light as input, with optical response reconstruction accuracy of 99%. 
    more » « less
  2. Optical metamaterials manipulate light through various confinement and scattering processes, offering unique advantages like high performance, small form factor and easy integration with semiconductor devices. However, designing metasurfaces with suitable optical responses for complex metamaterial systems remains challenging due to the exponentially growing computation cost and the ill-posed nature of inverse problems. To expedite the computation for the inverse design of metasurfaces, a physics-informed deep learning (DL) framework is used. A tandem DL architecture with physics-based learning is used to select designs that are scientifically consistent, have low error in design prediction, and accurate reconstruction of optical responses. The authors focus on the inverse design of a representative plasmonic device and consider the prediction of design for the optical response of a single wavelength incident or a spectrum of wavelength in the visible light range. The physics-based constraint is derived from solving the electromagnetic wave equations for a simplified homogenized model. The model converges with an accuracy up to 97% for inverse design prediction with the optical response for the visible light spectrum as input, and up to 96% for optical response of single wavelength of light as input, with optical response reconstruction accuracy of 99%. 
    more » « less
  3. Advances in laser technology have driven discoveries in atomic, molecular, and optical (AMO) physics and emerging applications, from quantum computers with cold atoms or ions, to quantum networks with solid-state color centers. This progress is motivating the development of a new generation of optical control systems that can manipulate the light field with high fidelity at wavelengths relevant for AMO applications. These systems are characterized by criteria: (C1) operation at a design wavelength of choice in the visible (VIS) or near-infrared (IR) spectrum, (C2) a scalable platform that can support large channel counts, (C3) high-intensity modulation extinction and (C4) repeatability compatible with low gate errors, and (C5) fast switching times. Here, we provide a pathway to address these challenges by introducing an atom control architecture based on VIS-IR photonic integrated circuit (PIC) technology. Based on a complementary metal–oxide–semiconductor fabrication process, this atom-control PIC (APIC) technology can meet system requirements (C1)–(C5). As a proof of concept, we demonstrate a 16-channel silicon-nitride-based APIC with (5.8±0.4)ns response times and >30dB extinction ratio at a wavelength of 780 nm. 
    more » « less
  4. Abstract Metasurfaces have drawn considerable attentions for their revolutionary capability of tailoring the amplitude, phase, and polarization of light. By integrating the nonlinear optical processes into metasurfaces, new wavelengths are introduced as an extra degree of freedom for further advancing the device performance. However, most of the existing nonlinear plasmonic metasurfaces are based on metallic nanoantennas as meta‐atoms, suffering from strong background transmission, low laser damage threshold and small nonlinear conversion efficiency. Here, Babinet‐inverted plasmonic metasurfaces made of C‐shaped nanoapertures as meta‐atoms are designed and demonstrated to solve these issues. Rotation‐gradient nonlinear metasurfaces are further constructed for producing spin‐selective second‐harmonic vortex beams with the orbital angular momentum (OAM) and beam diffraction angle determined by both the spin states of the fundamental wave and second‐harmonic emission. The results enable new types of functional metasurface chips for applications in spin, OAM, and wavelength multiplexed optical trapping, all‐optical communication, and optical data storage. 
    more » « less
  5. Abstract Here, a wavelength‐specific photo‐thermoelectric (PTE) device is reported that achieves narrowband optical absorption and thermoelectric conversion functions using a stack of thin films on a grating‐patterned substrate. Conventional PTE devices are broadband with the absorption of electromagnetic radiation from ultraviolet to terahertz. There are demands for PTE devices that can exhibit narrowband response at a desired wavelength. Here, the narrowband PTE device consists of a photonic crystal (PC) filter with metal cladding and a thin‐film thermocouple. The PC‐PTE design is investigated numerically to illustrate the underlying energy conversion mechanism. The device is fabricated using nanoreplica molding followed by coating of thin films. The fabricated metal‐cladding PC resonator exhibits a narrowband optical absorption with a resonant absorption coefficient of 85.4% and full‐width‐half‐maximum of 14.8 nm in the visible wavelength range. The PTE measurements show that the thermoelectric output is sensitive to the coupling of incident light and guided‐mode resonance modes. Illuminated under the resonant condition, the PTE device exhibits a responsivity and noise equivalent power of 0.26 V W−1and 7.5 nW Hz−1/2, respectively. This PC‐PTE technology has the unique attributes of narrowband detection, large surface area, and low cost for the potential application in sensors, optical spectroscopy, and imaging. 
    more » « less