Machine-learning algorithms are powerful tools in developing reliable models to relate the design space of a nanophotonic structure to its response space. They can be used not only to simplify the inverse design problem but also to provide valuable insight about the physics of light-matter interaction. This talk will provide a new approach through combining manifold-learning algorithms for reducing the dimensionality of the problem with metric-learning techniques for more insightful mapping of the input-output relation to the dimensionality-reduced (or the latent) space. In addition to covering the fundamental properties of the presented algorithms, their applications to both the inverse design and the knowledge discovery in state-of-the-art metaphotonic structures will be discussed.
We present a new approach based on Bayesian neural networks (BNNs) for severity assessment of lung diseases using chest X-rays (CXRs). In contrast to reqular NNs, our model can provide uncertainty of the prediction for an input CXR which is crucial for clinical implementation of machine learning-assisted tools in radiology. With no loss of generality, we apply this method for severity assessment of COVID-19 pneumonia using multi-reader datasets from the USA and Korea. Our results show that the BNN can classify COVID-19 pneumonia with performance comparable to human experts while providing prediction uncertainty. We also compare the uncertainty of the model over different severity classes with inter-reader variability among the radiologists.
In this work, we present a new approach based on metric learning for defining new similarity measures that are well-matched for design tasks in nanophotonics. Majority of the existing approaches use mean squared error (MSE) or mean absolute error (MAE) as the similarity measure to compare the desired and optimal spectra while it is clear that point-wise distance cannot capture the important features of the responses. Here, our goal is to use deep metric learning to provide a systematic approach for defining new metrics in nanophotonics.
This talk is focused on using the intelligent aspects of machine learning (ML) for both the understanding of the subtle properties of nanophotonic devices and their inverse design to achieve a desired response. It will be shown that by reducing the dimensionality of the problem using manifold learning techniques and simplifying the resulting networks using pruning, the computation complexity of the underlying artificial intelligence (AI) algorithms will be considerably reduced. Furthermore, by optimally defining the loss function (or the metric) for AI algorithms, priceless information about the properties of photonic nanostructures can be uncovered while facilitating the better visualization of the input-output relationship in these nanostructures. In addition, the resulting manifold-learning algorithms can be optimally trained to facilitate the inverse design of such nanostructures while minimizing the structural complexity. This talk will provide the foundation for both knowledge discovery and design in photonic nanostructures using manifold learning and metric learning and their application to the highly desired metaphotonic structures as an example platform.
Here, we present a new approach based on manifold learning for inverse design and knowledge discovery in nanophotonics. We present the unique capabilities of manifold learning approaches for reducing the dimensionality of the high-dimensional relationships in photonic nanostructures. We show how this can help to understand the underlying patterns in the responses of such nanostructures. Such a visualization in the low-dimensional space enables knowledge discovery and studying the underlying physics of nanostructures and can facilitate the inverse design. We also use this method to study the role of the design parameters and design a class of nanostructure while reducing the design complexity.
We present a new machine learning (ML)-based approach for efficient inverse design of nanophotonic structures. Generating training data for a ML method is the most computationally expensive step in the ML-based inverse design and knowledge discovery, and it becomes cumbersome when the number of design parameters and the complexity of the structure increase. Here we show how to optimize the training process and considerably reduce the computation requirements without increasing error in order to efficiently model the input-output relationship in a nanophotonic structure and solve the inverse design problem.
A new deep-learning approach based on dimensionality reduction techniques for the design and knowledge discovery in nanophotonic structures will be presented. It is shown that reducing the dimensionality of the response and design spaces in a class of nanophotonic structures can provide new insight into the physics of light-matter interaction in such nanostructures while facilitating their inverse design. These unique features are achieved while considerably reducing the computation complexity through dimensionality reduction. It is also shown that this approach can enable an evolutionary design method in which the initial design can be evolved intelligently into an alternative with favorable specification like less complexity, more robustness, less power consumption, etc. In addition to providing the details about the fundamental aspects of the latent learning approach, its application to design of reconfigurable metasurfaces will be demonstrated.
We present a new approach for design of novel loss functions and introduce an optimal similarity-metric design for machine-learning-based design and knowledge discovery in nanophotonics. Machine-learning algorithms estimate the input-output relation in a photonic nanostructure by minimizing a loss function. We show that careful selection (from the available loss functions) or design of novel loss functions that are optimized for specific tasks can considerably improve the performance of machine-learning algorithms for design and knowledge discovery in photonic nanostructures. We also discuss the limitations and inefficacies of conventional loss functions that are currently being used for machine learning algorithms.
The systematic realization of the nature of the optical functionalities requires significant knowledge about the influence of nanostructure features on the propagation of electromagnetic waves. Due to the lack of such valuable information, cumbersome numerical calculations are currently the prevalent approach in designing nanostructures. In this talk, we introduce a novel technique based on manifold learning to reduce the complexity of the design problems. The developed algorithms provide valuable insights about the feasibility of a desired optical response and the roles of design parameters in forming the response through low-dimensional visualization. This extracted underlying information can be employed in different settings to accelerate the design of electromagnetic nanostructures for a wide range of applications.
We present a new approach based on manifold learning for breaking the geometrical complexity of the photonic nanostructures during solving the inverse design problem. By encoding the high-dimensional spectral responses of a class of nanostructures into the latent space, we provide intuitive information about the underlying physics of these structures. We discuss the relations between the non-Euclidean distances in the latent space and changes in the optical responses and relate the movements in the latent space to the modifications of the optical responses for a class of nanostructures. Finally, we provide a new approach to use the insight about the role of design parameters to design nanostructures with minimal design complexity for a given functionality.
This Conference Presentation, "Sample-efficient machine-learning method for designing photonic nanostructures," was recorded at Photonics West 2020 held in San Francisco, California, United States.
This Conference Presentation, "Deep-learning-based design of Fano resonant HfO2 metasurfaces for full color generation," was recorded at Photonics West 2020 held in San Francisco, California, United States.
We leverage a dimensionality reduction approach to develop a novel inverse design platform applicable to a wide class of optical nanoantennas. The proposed dimensionality reduction technique uses a high level of correlation (in frequency and space domains) in the propagation of electromagnetic waves to considerably reduce the dimensionality of the response space of the problem. In addition, the correlation that often exists among the effects of design parameters on the response of the structure (i.e., selecting more design parameters than needed for uniquely identifying a structure for a given input-output relation) is used to reduce the dimensionality of the design space. In addition to the considerable mitigation of computation time and complexity, the two key features of dimensionality reduction, i.e., : 1) the ability to train a NN and later use it for a large class of problems, and 2) the possibility of analytically relating the reduced design space to the original design space to obtain valuable intuitive information about the roles of each design parameter in the overall performance of the nanostructure, highlight the superiority of the proposed approach. This is in contrast to existing analysis and optimization techniques, which require an intensive repetition of the simulations for each design problem without providing an intuitive understanding of the roles of design parameters. As a proof of concept, we apply this approach to a nanoscale structural color recently emerged as a promising candidate to organic colors in the printing technology. To circumvent the high absorption loss and efficiency of plasmonic color generators, we harness the fundamental dipolar Mie resonances of an array of asymmetric titanium dioxide elliptical nanopillars. We will further experimentally demonstrate such an optimized polarization-sensitive all-dielectric significantly enhance the resolution, saturation, and hue of color palettes. Such a novel inverse design approach highlights the performance of machine learning based approaches in developing highly-efficient metastructures.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.