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View article: High Transmission Efficiency Hybrid Metal-Dielectric Metasurfaces for Mid-Infrared Spectroscopy
High Transmission Efficiency Hybrid Metal-Dielectric Metasurfaces for Mid-Infrared Spectroscopy Open
Mid-infrared (MIR) spectroscopy enables non-invasive identification of chemical species by probing absorption spectra associated with molecular vibrational modes, where spectral filters play a central role. Conventional plasmonic metasurfa…
View article: Design of hybrid metal-dielectric (Al–TiO<sub>2</sub>) metasurfaces RGB color filters
Design of hybrid metal-dielectric (Al–TiO<sub>2</sub>) metasurfaces RGB color filters Open
Color filter arrays play a vital role in spectrally discriminating light into red, green and blue (RGB) bands—widely utilized in color cameras and display technology. Existing absorptive dye color filters exhibit low transmission efficienc…
View article: High‐Transmission Mid‐Infrared Bandpass Filters using Hybrid Metal‐Dielectric Metasurfaces for CO<sub>2</sub> Sensing
High‐Transmission Mid‐Infrared Bandpass Filters using Hybrid Metal‐Dielectric Metasurfaces for CO<sub>2</sub> Sensing Open
Mid‐infrared (MIR) spectroscopy is widely applied in many applications such as gas sensing, industrial inspection, astronomy, and imaging. While thin‐film narrowband interference filters are cost‐effective for MIR sensing, their complex fa…
View article: High-Transmission Mid-Infrared Bandpass Filters Using Hybrid Metal-Dielectric Metasurfaces for CO2 Sensing
High-Transmission Mid-Infrared Bandpass Filters Using Hybrid Metal-Dielectric Metasurfaces for CO2 Sensing Open
Mid-infrared (MIR) spectroscopy is a powerful technique employed for a variety of applications, including gas sensing, industrial inspection, astronomy, surveillance, and imaging. Thin-film narrowband interference filters, targeted to spec…
View article: Hyperpixels: Pixel Filter Arrays of Multivariate Optical Elements for Optimized Spectral Imaging
Hyperpixels: Pixel Filter Arrays of Multivariate Optical Elements for Optimized Spectral Imaging Open
We introduce the concept of `hyperpixels' in which each element of a pixel filter array (suitable for CMOS image sensor integration) has a spectral transmission tailored to a target spectral component expected in application-specific scene…
View article: Versatile spaceborne photonics with chalcogenide phase-change materials
Versatile spaceborne photonics with chalcogenide phase-change materials Open
Recent growth in space systems has seen increasing capabilities packed into smaller and lighter Earth observation and deep space mission spacecraft. Phase-change materials (PCMs) are nonvolatile, reconfigurable, fast-switching, and have re…
View article: Versatile spaceborne photonics with chalcogenide phase-change materials
Versatile spaceborne photonics with chalcogenide phase-change materials Open
Recent growth in space systems has seen increasing capabilities packed into smaller and lighter Earth observation and deep space mission spacecraft. Phase-change materials (PCMs) are nonvolatile, reconfigurable, fast-switching, and have re…
View article: Multispectral imaging of nailfold capillaries using light-emitting diode illumination
Multispectral imaging of nailfold capillaries using light-emitting diode illumination Open
SIGNIFICANCE: The capillaries are the smallest blood vessels in the body, typically imaged using video capillaroscopy to aid diagnosis of connective tissue diseases, such as systemic sclerosis. Video capillaroscopy allows visualization of …
View article: Deep neural network enabled active metasurface embedded design
Deep neural network enabled active metasurface embedded design Open
In this paper, we propose a deep learning approach for forward modeling and inverse design of photonic devices containing embedded active metasurface structures. In particular, we demonstrate that combining neural network design of metasur…
View article: Spectrally tailored 'hyperpixel' filter arrays for imaging of chemical compositions
Spectrally tailored 'hyperpixel' filter arrays for imaging of chemical compositions Open
We present a method for designing and fabricating 'HyperPixels': pixel filter arrays with custom spectral transmission properties that enable efficient imaging of specific chromophores or fluorophores. Multispectral imaging typically targe…
View article: Optimizing achromaticity in metalenses, and development of a layered thin-film metalens
Optimizing achromaticity in metalenses, and development of a layered thin-film metalens Open
Metalenses are ultrathin optical devices designed to replicate behavior of conventional refractive lenses, or lens arrays, utilizing nanoscale resonant structures to redirect incident light. These are often comprised of discrete meta-atoms…
View article: Opti-MSFA: a toolbox for generalized design and optimization of multispectral filter arrays.
Opti-MSFA: a toolbox for generalized design and optimization of multispectral filter arrays. Open
Multispectral imaging captures spatial information across a set of discrete spectral channels and is widely utilized across diverse applications such as remote sensing, industrial inspection, and biomedical imaging. Multispectral filter ar…
View article: Automated real-time spectral characterization of phase-change tunable filters using a linear variable filter and IR camera for wide-field MWIR imaging
Automated real-time spectral characterization of phase-change tunable filters using a linear variable filter and IR camera for wide-field MWIR imaging Open
Actively tunable optical filters based on chalcogenide phase-change materials (PCMs) are an emerging technology with applications across chemical spectroscopy and thermal imaging. The refractive index of an embedded PCM thin film is modula…
View article: PCM-net: a refractive index database of chalcogenide phase change materials for tunable nanophotonic device modelling
PCM-net: a refractive index database of chalcogenide phase change materials for tunable nanophotonic device modelling Open
The growing demand for multifunctional nanophotonic devices has led to the exploration, and utilization, of a plethora of exotic electro-optical materials. Recently, chalcogenide glass based phase change materials (PCMs) have shown utility…
View article: Automated real-time spectral characterization of phase-change tunable optical filters using a linear variable filter and infrared camera
Automated real-time spectral characterization of phase-change tunable optical filters using a linear variable filter and infrared camera Open
Actively tunable optical filters based on chalcogenide phase-change materials (PCMs) are an emerging technology with applications across chemical spectroscopy and thermal imaging. The refractive index of an embedded PCM thin film is modula…
View article: PCM-net: A refractive index database of chalcogenide phase change\n materials for tunable nanophotonic device modelling
PCM-net: A refractive index database of chalcogenide phase change\n materials for tunable nanophotonic device modelling Open
Recently, chalcogenide glass based phase change materials (PCMs) have shown\nutility as a tuning material for a range of nanophotonic devices. Owing to\ntheir low loss, ultrafast switching speeds and wide waveband operation, PCMs\nare inte…
View article: Reversible optical tuning of GeSbTe phase-change metasurface spectral filters for mid-wave infrared imaging
Reversible optical tuning of GeSbTe phase-change metasurface spectral filters for mid-wave infrared imaging Open
Tunable narrowband spectral filtering across arbitrary optical wavebands is highly desirable in a plethora of applications, from chemical sensing and hyperspectral imaging to infrared astronomy. Yet, the ability to reconfigure the optical …
View article: Tunable mid-wave infrared Fabry-Perot bandpass filters using phase-change GeSbTe.
Tunable mid-wave infrared Fabry-Perot bandpass filters using phase-change GeSbTe. Open
We demonstrate spectrally-tunable Fabry-Perot bandpass filters operating across the MWIR by utilizing the phase-change material GeSbTe (GST) as a tunable cavity medium between two (Ge:Si) distributed Bragg reflectors. The induced refractiv…
View article: Supplementary document for Reversible optical tuning of GeSbTe phase-change metasurface spectral filters for mid-wave infrared imaging - 4598120.pdf
Supplementary document for Reversible optical tuning of GeSbTe phase-change metasurface spectral filters for mid-wave infrared imaging - 4598120.pdf Open
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View article: All-optical continuous tuning of phase-change plasmonic metasurfaces for multispectral thermal imaging
All-optical continuous tuning of phase-change plasmonic metasurfaces for multispectral thermal imaging Open
Actively tunable, narrowband spectral filtering across arbitrary optical wavebands is highly desirable in a plethora of applications, from chemical sensing, hyperspectral imaging to infrared astronomy. Yet, the ability to actively reconfig…
View article: Quantitative phase and polarization imaging through an optical fiber applied to detection of early esophageal tumorigenesis
Quantitative phase and polarization imaging through an optical fiber applied to detection of early esophageal tumorigenesis Open
Phase and polarization of coherent light are highly perturbed by interaction with microstructural changes in premalignant tissue, holding promise for label-free detection of early tumors in endoscopically accessible tissues such as the gas…
View article: Characterizing Optical Fiber Transmission Matrices Using Metasurface Reflector Stacks for Lensless Imaging without Distal Access
Characterizing Optical Fiber Transmission Matrices Using Metasurface Reflector Stacks for Lensless Imaging without Distal Access Open
© 2019 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the "https://creativecommons.org/licenses/by/4.0/" Creative Commons Attribution 4.0 International license. Further di…
View article: Dataset for: Grayscale-to-color: Scalable fabrication of custom multispectral filter arrays.
Dataset for: Grayscale-to-color: Scalable fabrication of custom multispectral filter arrays. Open
Raw data for the results (Figures) in the main manuscript.\n\nDataset description (4-sub folders):\n\nSub-folder 1 > AFM data: contains the .ibw files of the surface morphology of the samples shown in the Figures of main manuscript (listed…
View article: Grayscale-to-Color: Scalable Fabrication of Custom Multispectral Filter Arrays.
Grayscale-to-Color: Scalable Fabrication of Custom Multispectral Filter Arrays. Open
Snapshot multispectral image (MSI) sensors have been proposed as a key enabler for a plethora of multispectral imaging applications, from diagnostic medical imaging to remote sensing. With each application requiring a different set, and nu…
View article: Single-nanowire spectrometers
Single-nanowire spectrometers Open
Miniaturizing spectrometers Spectroscopy is a ubiquitous characterization tool spanning most scientific and many industrial disciplines. Most handheld spectrometers are based on tabletop optical components, which limits the scale to which …
View article: Data for: Single-nanowire spectrometers
Data for: Single-nanowire spectrometers Open
Data for the plots in the main text. Instructions for some data sets are contained within the Excel file. \nDetailed description:\nOne Microsoft Excel file containing data for each plot in the main manuscript figures, as labelled. Photolum…
View article: Full-field quantitative phase and polarisation-resolved imaging through an optical fibre bundle
Full-field quantitative phase and polarisation-resolved imaging through an optical fibre bundle Open
Flexible optical fibres, used in conventional medical endoscopy and industrial inspection, scramble phase and polarisation information, restricting users to amplitude-only imaging. Here, we exploit the near-diagonality of the multi-core fi…
View article: The dataset for "Measuring chirality in the far-field from a racemic nanomaterial: diffraction spectroscopy from plasmonic nanogratings"
The dataset for "Measuring chirality in the far-field from a racemic nanomaterial: diffraction spectroscopy from plasmonic nanogratings" Open
This dataset contains data on gold plasmonic nanogratings used for diffraction circular intensity difference spectroscopy. The data was collected to first characterise the various nanogratings studied using atomic force microscopy - the na…