Related papers: Carbon dioxide absorption spectroscopy with a mid-…
Carbon monoxide (CO) is a significant indicator gas with considerable application value in atmospheric monitoring, industrial production and medical diagnosis. Its fundamental vibrational band locates around 4.6 $\upmu$m and has larger…
Detection sensitivity is one of the most important attributes to consider during selection of spectroscopic techniques. However, high sensitivity alone is insufficient for spectroscopic measurements in spectrally congested regions.…
Mid-infrared absorption spectroscopy is a well-established technique for non-destructive quantitative molecular analysis. Waveguide-integrated sensors provide a particularly compact solution operating with reduced sample volumes while…
In this paper we report suspended silicon waveguides operating at a wavelength of 7.67 mm with a propagation loss of 3.1 ? 0.3 dB/cm. To our knowledge this is the first demonstration of low loss silicon waveguides at such a long wavelength,…
The use of optics in microelectronic circuits to overcome the limitation of metallic interconnects is more and more considered as a viable solution. Among future silicon compatible materials, carbon nanotubes are promising candidates thanks…
Silicon is an extremely attractive material platform for integrated optics at telecommunications wavelengths, particularly for integration with CMOS circuits. Developing detectors and electrically pumped lasers at telecom wavelengths are…
A mid-Infrared frequency comb is produced via an optical parametric oscillator (OPO) pumped by an amplified 100 MHz Yb:fiber mode-locked laser. We use this source to make measurements of the concentration of the atmospherically-relevant…
It has recently been shown that silicon nanophotonic waveguides can be used to construct all of the components of a photonic data transmission system on a single chip. These components can be integrated together with CMOS electronics to…
We report on a comb-locked cavity ring-down spectrometer developed for high-precision, SI-traceable, molecular spectroscopy of air-broadened CO2 gas samples. The experimental setup relies on the use of a singly-resonant optical parametric…
Silicon photonics is being extended from the near-infrared (near-IR) window of 1.3-1.5 {\mu}m for optical fiber communications to the mid-infrared (mid-IR) wavelength-band of 2 {\mu}m or longer for satisfying the increasing demands in many…
Monitoring of radiocarbon ($^{14}$C) in carbon dioxide is demonstrated using mid-infrared spectroscopy and a quantum cascade laser. The measurement is based on cavity ring-down spectroscopy, and a high sensitivity is achieved with a simple…
Broadband mid-infrared light sources are highly desired for wide-ranging applications that span free-space communications to spectroscopy. In recent years, silicon has attracted great interest as a platform for nonlinear optical wavelength…
The development of compact and fieldable mid-infrared (mid-IR) spectroscopy devices represents a critical challenge for distributed sensing with applications from gas leak detection to environmental monitoring. Recent work has focused on…
Research activities during the last decade have shown the strong potential of photonic devices to greatly simplify ground based and space borne astronomical instruments and to improve their performance. We focus specifically on the…
Broadband mid-infrared (mid-IR) spectroscopy applications could greatly benefit from today's well-developed, highly scalable silicon photonics technology; however, this platform lacks broadband transparency due to its reliance on absorptive…
The $\lambda$ = 2.06 $\mu$m absorption band of CO$_2$ is widely used for the remote sensing of atmospheric carbon dioxide, making it relevant to many important top-down measurements of carbon flux. The forward models used in the retrieval…
Whispering gallery mode (WGM) microcavities feature ultrahigh Q-factors and small mode volumes, offering strong light-matter interactions for sensing applications. However, unmodified surfaces are weakly responsive togas-phase refractive…
Wide bandgap semiconductors are widely used in photonic technologies due to their advantageous features, such as large optical bandgap, low losses, and fast operational speeds. Silicon carbide is a prototypical wide bandgap semiconductor…
Nanophotonic waveguides with sub-wavelength mode confinement and engineered dispersion profiles are an excellent platform for application-tailored nonlinear optical interactions at low pulse energies. Here, we present fully air clad…
With the recent radioastronomical detection of cis-trans-carbonic acid (H$_2$CO$_3$) in a molecular cloud toward the galactic center, the more stable but currently unobserved cis-cis conformer is shown here to have strong IR features. While…