Frequency Comb Vernier Spectroscopy for Broadband, High-Resolution, High-Sensitivity Absorption and Dispersion Spectra

Mid-infrared frequency comb for broadband high precision and sensitivity molecular spectroscopy.

We report on the experimental demonstration of the metrological and spectroscopic performances of a mid-infrared comb generated by a nonlinear downconversion process from a Ti:sapphire-based near-infrared comb. A quantum cascade laser at 4330 nm was phase-locked to a single tooth of this mid-infrared comb and its frequency-noise power spectral density was measured. The mid-infrared comb itself ...

Direct Frequency Comb Spectroscopy and High - Resolution Coherent Control

Continuous Vernier filtering of an optical frequency comb for broadband cavity-enhanced molecular spectroscopy

We have recently introduced the Vernierbased Direct Frequency Comb Cavity-Enhanced Spectroscopy technique and we present the corresponding formalism for quantitative broadband spectroscopy. We achieve high sensitivity and broadband performance by acquiring spectra covering more than 2000 cm−1 around 12600 cm−1 (800 nm), resolving the 3ν+δ band of water vapor and the entire A-band of oxygen in a...

Implementation of continuous filtering frequency comb Vernier spectroscopy for continuous acquisition of spectra in a flame

In this project laser absorption spectroscopy was performed on a flame in a FabryPérot cavity, using an optical frequency comb. Optical frequency comb spectroscopy is a technique that allows broadband ultra-sensitive detection of molecular species in gas phase. Optical frequency combs are generated by femtosecond mode-locked lasers, which generate short pulses and whose spectrum consists of a c...

High-frequency Broadband Modulations of Electroencephalographic Spectra

High-frequency cortical potentials in electroencephalographic (EEG) scalp recordings have low amplitudes and may be confounded with scalp muscle activities. EEG data from an eyes-closed emotion imagination task were linearly decomposed using independent component analysis (ICA) into maximally independent component (IC) processes. Joint decomposition of IC log spectrograms into source- and frequ...