Publications related to Index-matching material

van der Waals Materials for Overcoming Fundamental Limitations in Photonic Integrated Circuitry

With the advance of on-chip nanophotonics, there is a high demand for high-refractive-index and low-loss materials. Currently, this technology is dominated by silicon, but van der Waals (vdW) materials with a high refractive index can offer a very advanced ...

AMER CHEMICAL SOC2023

Nanoscale local modification of PMMA refractive index by tip-enhanced femtosecond pulsed laser irradiation

Mihai Adrian Ionescu

Tip-enhanced optical effects have enabled a wide palette of nanoscale investigation techniques and recently they were successfully used to modify and manipulate matter with nanoscale spatial resolution. We contribute to this latter area by reporting a viab ...

ELSEVIER2023

Glass-in-glass infiltration for 3D micro-optical composite components

Andreas Mortensen, Yves Bellouard, Jérôme Faist, Gözden Torun, Enrico Casamenti, Luciano Borasi, Mathieu Bertrand

Chalcogenide glass exhibits a wide transmission window in the infrared range, a high refractive index, and nonlinear optical properties; however, due to its poor mechanical properties and low chemical and environmental stability, producing three-dimensiona ...

2022

3D reconstruction of weakly scattering objects from 2D intensity-only measurements using the Wolf transform

Demetri Psaltis, Joowon Lim, Elizabeth Elena Antoine, Ahmed Ayoub

A new approach to optical diffraction tomography (ODT) based on intensity measurements is presented. By applying the Wolf transform directly to intensity measurements, we observed unexpected behavior in the 3D reconstruction of the sample. Such a reconstru ...

2021

Polarization-sensitive optics diffraction tomography

Demetri Psaltis, Joowon Lim, Elizabeth Elena Antoine, Amirhossein Saba Shirvan, Ahmed Ayoub

Polarization of light has been widely used as a contrast mechanism in two-dimensional (2D) microscopy and also in some three-dimensional (3D) imaging modalities. In this paper, we report the 3D tomographic reconstruction of the refractive index (RI) tensor ...

2021

Optical phase contrast imaging of human retinal cells by changing the tissue refractive index

Christophe Moser, Timothé Laforest, Laura Emmanuelle Kowalczuk, Mathieu Künzi

Purpose : Based on oblique partially coherent illumination of transparent samples, we developed a simple custom Optical Phase Imaging (OPI) microscope providing a label-free, semi-quantitative phase contrast imaging. The aim of this study was to explore th ...

ASSOC RESEARCH VISION OPHTHALMOLOGY INC2020

Scanning PIV of turbulent flows over and through rough porous beds using refractive index matching

Christophe Ancey, Gauthier Paul Daniel Marie Rousseau

This paper presents image velocimetry measurements on turbulent flows adjacent to a permeable bed made of randomly packed glass particles. For measuring flow velocities inside the bed, the refractive index of the glass particles was matched with that of th ...

SPRINGER2020

Formation Rules and Dynamics of Photoinduced χ(2) Gratings in Silicon Nitride Waveguides

Tobias Kippenberg, Camille Sophie Brès, Davide Grassani, Martin Hubert Peter Pfeiffer, Edgars Nitiss, Tianyi Liu

Silicon nitride has emerged as a prominent platform for building photonics integrated circuits. While its nonlinear properties based on third-order effects have been successfully exploited, an efficient second harmonic generation in standard stoichiometric ...

2020

Tomographic imaging with harmonic holography in tissues of known refractive index distribution

Demetri Psaltis, Ye Pu

High-resolution imaging in thick biological tissues beyond a few transport mean free path of photons remains a formidable challenge to modern science and technology. Recent advancements in optical tomography have enabled the reconstruction of the three-dim ...

SPIE-INT SOC OPTICAL ENGINEERING2018

Experimental investigation of the propagation properties of Bloch surface waves on dielectric multilayer platform

Hans Peter Herzig, Elsie Barakat, Richa Dubey

Background: The periodic dielectric multilayers sustaining Bloch surface waves have been proposed as a platformfor the sensing applications and the two dimensional integrated optics. In this paper, we present the experimental and theoretical investigation ...

2017

High-Q surface modes in photonic crystal/iron garnet film heterostructures for sensor applications

Giovanni Dietler, Serguei Sekatski, Pavel Kapralov

A novel type of a plasmonic sensor based on a magnetophotonic plasmonic heterostructure with an ultrahigh-Q resonance is considered. A magnetoplasmonic resonance with an angular width of 0.06A degrees, which corresponds to a Q factor of 700 and is a record ...

Springer Verlag2017

SIMToolbox: a MATLAB toolbox for structured illumination fluorescence microscopy

Tomas Lukes

SIMToolbox is an open-source, modular set of functions for MATLAB equipped with a user-friendly graphical interface and designed for processing two-dimensional and three-dimensional data acquired by structured illumination microscopy (SIM). Both optical se ...

Oxford University Press2016

System for optical detection and imaging of sub-diffraction-limited nano-objects

Martinus Gijs, Matteo Cornaglia, Hui Yang

Nano-objects (8) with feature size smaller than the classical Abbe's diffraction limit can be optically detected via a microlens (4) array configured in a miniaturized microfluidic device. A hydrophilic microwell (3) array in a hydrophobic layer (2) is fir ...

2016

Transition of optical regime in miniaturized optical systems: light interactions beyond the refraction limit

Hans Peter Herzig, Toralf Scharf, Myun Sik Kim

We investigate the transition of optical regimes of miniaturized optical systems using two canonical examples, where the refraction of light limits the system performance. A ball-lens and a solid immersion lens (SIL) are considered, whose refractive respon ...

Spie-Int Soc Optical Engineering2016

Super-Resolution Imaging of a Dielectric Microsphere Is Governed by the Waist of Its Photonic Nanojet

Martinus Gijs, Raphaël Etienne Jean Trouillon, Hui Yang, Gergely Huszka

Dielectric microspheres with appropriate refractive index can image objects with super-resolution, that is, with a precision well beyond the classical diffraction limit. A microsphere is also known to generate upon illumination a photonic nanojet, which is ...

American Chemical Society2016

Studies of hygrothermal degradation of a single fiber composite: An iterative approach with embedded optical sensors and numerical analysis

John Botsis, Marco Lai, Joël Cugnoni

The hydrothermal ageing of glass/epoxy interface is investigated using an experimental numerical approach on cylindrical epoxy specimens with centrally located optical fibers. A 24 mm long Bragg grating sensor is inscribed on the optical fiber and used to ...

Elsevier2014

Constrained regularized reconstruction of X-ray-DPCI tomograms with weighted-norm

Michaël Unser, Cédric René Jean Vonesch, Peter Modregger, Masih Nilchian, Stamatios Lefkimmiatis, Marco Stampanoni

In this paper we introduce a new reconstruction algorithm for X-ray differential phase-contrast Imaging (DPCI). Our approach is based on 1) a variational formulation with a weighted data term and 2) a variable-splitting scheme that allows for fast converge ...

Optical Society of America2013

A Psf-Based Approach To Biplane Calibration In 3D Super-Resolution Microscopy

Michaël Unser, Suliana Manley, Daniel Sage, Hagay Kirshner, Thomas Pengo

Super-resolution localization microscopy methods such as PALM and STORM have been shown to provide imaging with resolutions up to a few tens of nanometers while using relatively simple setups. Biplane PALM has extended the PALM technique to three-dimension ...

Ieee2012

Novel biosensor for detecting Hemoglobin and its oxidation state based on nonreciprocity in a coupled waveguide system

Olivier Martin, Shourya Dutta Gupta

We study the reflection of a tightly focused Gaussian beam off a near symmetric resonant tunneling structure comprising two identical coupled waveguides. The coupled waveguides are loaded on each side by a spacer layer and a high index prism. Reflection of ...

Spie-Int Soc Optical Engineering, Po Box 10, Bellingham, Wa 98227-0010 Usa2012

Fabrication of Bragg gratings in microstructured and step index Bi-SiO2 optical fibers using an ArF laser

Hans Georg Limberger, Georgios Violakis

An ArF excimer laser was used to fabricate Bragg gratings in fibers with Bi-SiO2 core and microstructured or F-doped claddings without fiber presensitization. Average and modulated refractive index changes of 2.7 x 10(-4) and 1.0 x 10(-4) were induced in p ...

Optical Society of America2012