Related papers: Broadband calibration-free cavity-enhanced complex…
We report the broadband absorption spectrum of the $3\nu_{2}$ band of $^{14}$NH$_{3}$ near 4 $\mu m$. The data were recorded using a mid-infrared frequency comb coupled to a homebuilt Fourier-transform spectrometer with a resolution of…
Fourier transform spectroscopy based on incoherent light sources is a well-established tool in research fields from molecular spectroscopy and atmospheric monitoring to material science and biophysics. It provides broadband molecular…
Wideband spectrum sensing is becoming increasingly important to cognitive radio (CR) systems for exploiting spectral opportunities. This paper introduces a novel multi-rate sub-Nyquist spectrum sensing (MS3) system that implements…
Optical frequency combs have the potential to improve the precision of the radial velocity measurement of celestial bodies, leading to breakthroughs in such fields as exoplanet exploration. For these purposes, the comb must have a broad…
We present a novel axial ptychographic coherent diffractive imaging (AP-CDI) technique designed to overcome the critical throughput bottleneck of conventional methods. By replacing the 2D raster scan with a simple 1D axial scan, our…
Near-infrared (NIR) hyperspectral imaging has become a critical tool in modern analytical science. However, conventional NIR hyperspectral imaging systems face challenges including high cost, bulky instrumentation, and inefficient data…
We propose and experimentally demonstrate a fiber spectrum analyzer based on a planar waveguide chip butt-coupled with an input fiber and aligned to a standard camera without any free-space optical elements. The chip consists of a…
Optical spectroscopy and imaging of microscopic samples have opened up a wide range of applications throughout the physical, chemical, and biological sciences. High chemical specificity may be achieved by directly interrogating the…
This work introduces a novel reinterpretation of structured illumination (SI) microscopy for coherent imaging that allows three-dimensional imaging of complex refractive index (RI). To do so, we show that coherent SI is mathematically…
Dual comb spectroscopy allows for high-resolution spectra to be measured over broad bandwidths, but an essential requirement for coherent integration is the availability of a phase reference. Usually, this means that the combs' phase and…
We present a versatile mid-infrared frequency comb spectroscopy system based on a doubly resonant optical parametric oscillator tunable in the 3-5.4 {\mu}m range and two detection methods, a Fourier transform spectrometer (FTS) and a…
Dual-comb spectroscopy (DCS) is a powerful Fourier-transform spectroscopic technique that provides high-speed, high-resolution, and broadband measurements without moving parts. However, the high peak power of mode-locked pulses limits the…
On-chip spectroscopy that could realize real-time fingerprinting with label-free and high-throughput detection of trace molecules is one of the 'holy grails" of sensing. Such miniaturized spectrometers would greatly enable applications in…
We explore broadband and omnidirectional low frequency sound screening based on locally resonant acoustic metamaterials. We show that the coupling of different resonant modes supported by Fabry-Perot cavities can efficiently generate…
We have developed a conceptually new type of ellipsometry which allows the determination of the complex refractive index by simultaneously measuring the unpolarized normal-incidence reflectivity relative to the vacuum and to another…
Absorption spectroscopy is widely used in sensing and astronomy to understand molecular compositions on microscopic to cosmological scales. However, typical dispersive spectroscopic techniques require multichannel detection, fundamentally…
We demonstrate a quantitative broadband fiber sensor, based on evanescent field sensing in the cladding holes of an air-suspended solid-core photonic crystal fiber. We discuss the fabrication process, together with the structural- and…
We present a new cavity-based polarimetric scheme for highly sensitive and time-resolved measurements of birefringence and dichroism, linear and circular, that employs rapidly-pulsed single-frequency CW laser sources and extends current…
In this paper, we introduce an all-fibered dual-comb spectrometer based on a new design of highly nonlinear fiber to efficiently convert frequency combs from 1.55 micron to 2 micron We show that our spectrometer can be used to measure…
Optical frequency combs have had a remarkable impact on precision spectroscopy. Enabling this technology in the x-ray domain is expected to result in wide-ranging applications, such as stringent tests of astrophysical models and quantum…