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Displaying 1 - 9 of 9

Nonlinear Silicon waveguides produce tunable frequency combs spanning 2.0-8.5 ?m

September 25, 2019
Author(s)
Nima Nader, Abijith S. Kowligy, Jeffrey T. Chiles, Eric J. Stanton, Henry R. Timmers, Alexander J. Lind, Kimberly Briggman, Scott Diddams, Flavio Caldas da Cruz, Richard Mirin, Sae Woo Nam, Daniel M. Lesko
We present fully air clad suspended-silicon waveguides for efficient nonlinear interactions limited only by the silicon transparency. Novel fork-shaped couplers provide efficient input (

Infrared electric-field sampled frequency comb spectroscopy

June 7, 2019
Author(s)
Abijith S. Kowligy, Henry R. Timmers, Alexander Lind, Ugaitz Elu, Flavio Caldas da Cruz, Peter Schunemann, Jens Biegert, Scott Diddams
Molecular spectroscopy in the mid-infrared portion of the electromagnetic spectrum (3--25 um) has been a cornerstone interdisciplinary analytical technique widely adapted across the biological, chemical, and physical sciences. Applications range from

Octave-spanning dual frequency comb spectroscopy in the molecular fingerprint region

June 4, 2018
Author(s)
Henry R. Timmers, Abijith S. Kowligy, Alexander J. Lind, Flavio Caldas da Cruz, Nima Nader, Myles C. Silfies, Thomas K. Allison, Gabriel G. Ycas, Peter G. Schunemann, Scott B. Papp, Scott A. Diddams
Spectroscopy in the molecular fingerprint spectral region (6.5-20 $\mu$m) yields critical information on material structure for physical, chemical and biological sciences. Despite decades of effort, this portion of the electromagnetic spectrum remains

Mid-infrared frequency comb generation via cascaded quadratic nonlinearities in quasi-phase-matched waveguides

April 5, 2018
Author(s)
Abijith S. Kowligy, Alexander J. Lind, Daniel D. Hickstein, David R. Carlson, Henry R. Timmers, Nima Nader, Flavio Caldas da Cruz, Gabriel G. Ycas
We demonstrate mid-infrared (MIR) frequency comb generation in periodically poled lithium niobate (PPLN) waveguides pumped by nanojoule pulses from a 1.5 um mode-locked Er:fiber laser. The cascaded-c(2) nonlinearity in PPLN yields a nearly octave-spanning

Versatile silicon-waveguide supercontinuum for coherent mid-infrared spectroscopy

March 6, 2018
Author(s)
Nima Nader, Daniel Maser, Flavio Caldas da Cruz, Abijith S. Kowligy, Henry R. Timmers, Jeffrey T. Chiles, Connor D. Fredrick, Daron A. Westly, Richard P. Mirin, Jeffrey M. Shainline, Scott A. Diddams
Infrared spectroscopy is a powerful tool for basic and applied science. The rich “spectral fingerprints” of compounds in the 3 um - 20 um region provide a means to uniquely identify the molecular structure for applications that include fundamental

Coherent Frequency Combs for Spectroscopy in the 3-5 Micron Region

April 18, 2017
Author(s)
Daniel I. Maser, Gabriel G. Ycas, William I. Depetri, Flavio Caldas da Cruz, Scott A. Diddams
A tunable mid-infrared frequency comb was created via diff erence frequency generation. Pulses between 1 and 1.5 μm were mixed to make idlers of 2.6-5.2 μm. Two such combs were heterodyned at 5 μm to show their coherence and potential for spectroscopy.

Adaptive Terahertz Dual Frequency Comb Spectrometer

December 26, 2016
Author(s)
Flavio Caldas da Cruz, Francisco S. Vieira, David F. Plusquellic, Scott A. Diddams
Terahertz dual frequency comb spectroscopy (THz-DFCS) yields high spectral resolution without compromising bandwidth. Nonetheless, the resolution of THz-DFCS is usually limited by the laser repetition rate, which is typically between 80 MHz and 1 GHz. In

Rapid, broadband spectroscopic temperature measurement of CO 2 using VIPA spectroscopy

January 28, 2016
Author(s)
Andrew M. Klose, Gabriel Ycas, Flavio Caldas da Cruz, Daniel I. Maser, Scott Diddams
Rapid spectroscopic temperature measurements of a sealed carbon dioxide sample cell were realized with an optical frequency comb combined with a two-dimensional dispersive spectrometer. A supercontinuum laser source based on an erbium mode-locked laser was

Mid-Infrared Optical Frequency Combs based on Difference Frequency Generation for Dual-Comb Spectroscopy

May 10, 2015
Author(s)
Flavio Caldas da Cruz, Daniel I. Maser, Todd Johnson, Gabriel G. Ycas, Andrew M. Klose, Fabrizio R. Giorgetta, Ian R. Coddington, Nathan R. Newbury, Scott A. Diddams
Mid-infrared femtosecond optical frequency combs at 2.8 - 3.5 υm were produced by difference frequency generation of the spectral components of a near-infrared comb in a 3-mm long MgO:PPLN crystal. We observe strong pump depletion and 9.3 dB parametric