Coherent dual-comb interferometry with quasi-integer-ratio repetition rates.

We demonstrate a generalized method for dual-comb interferometry that involves the use of two frequency combs with quasi-integer-ratio repetition rates. We use a 16.67 MHz comb to probe an 80-cm-long ring cavity and a 100 MHz comb to asynchronously sample its impulse response.

Light field camera as a Fourier transform spectrometer sensor: instrument characterization and passive spectral ranging.

This paper presents a concept using field cameras in combination with Fourier transform spectrometers. The device can produce five-dimensional (position-angle-spectra) data cubes. This can lead to accurate measurements in both spectrum and distance and allows a thorough characterization of the interferometer, as well as adds passive ranging information to hyperspectral images.

Range-resolved vibrometry using a frequency comb in the OSCAT configuration.

Two methods for performing range-resolved vibrometry measurements using frequency combs are presented. A modified correction algorithm taking into account the differences from the typical dual comb spectroscopic technique is developed. Results are presented showing the recovery of a human voice sample and other sounds from different vibrating surfaces, including a diffuse wall and a glass slab.

Chemical detection with hyperspectral lidar using dual frequency combs.

High-resolution spectral lidar measurements using dual frequency combs as a source is presented. The technique enables the range-resolved measurement of fine spectral features, such as gas absorption lines, provided that a suitable scatterer is present in the scene. Measurements of HCN absorption lines at 20 meters are presented, with a water droplet cloud and a diffusely reflective surface as scatterers.

Fully referenced single-comb interferometry using optical sampling by laser-cavity tuning.

The correction of setup and laser instabilities in a single-comb interferometric measurement using optical sampling by laser-cavity tuning is investigated. A two-reference solution that allows full correction of the interferogram is presented. The technique is compared to a slightly simpler one-reference correction.

Referenced passive spectroscopy using dual frequency combs.

A referenced passive spectroscopy scheme using infrared frequency combs is presented. We perform a noise analysis and compare the results with a classical Fourier transform spectrometer. Experimental results are shown and great agreement with theory is obtained.

Experimental demonstration of ultrafast all-fiber high-order photonic temporal differentiators.

We propose and demonstrate what we believe to be a new, simple, and compact all-fiber design for arbitrary-order ultrafast optical temporal differentiation. The proposed design allows us to implement any desired differentiation order using a maximum of two concatenated fiber gratings, both operating in transmission. A single specially apodized chirped fiber Bragg grating is required for implementing any even-order differentiator, whereas the immediately next odd-order differentiator can be implemented by concatenating a long-period fiber-grating first-order differentiator.