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Search Publications by: Abijith Kowligy (Assoc)

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Displaying 1 - 13 of 13

Fully phase-stabilized 1 GHz turnkey frequency comb at 1.5 mm

March 15, 2021
Author(s)
Daniel Lesko, Alexander Lind, Nazanin Hoghooghi, Abijith S. Kowligy, Henry R. Timmers, Pooja Sekhar, Benjamin Rudin, Florian Emaury, Gregory B. Rieker, Scott Diddams
Low noise and high repetition rate optical frequency combs have been desirable for many applications from timekeeping to precision spectroscopy. With higher power per comb mode, gigahertz repetition rates enable rapid spectroscopic sensing in a dual-comb

A six-octave optical frequency comb from a scalable few-cycle Erbium fiber laser

March 11, 2021
Author(s)
Daniel Lesko, Henry R. Timmers, Sida Xing, Abijith S. Kowligy, Alexander Lind, Scott Diddams
A coherent, compact and robust light source with coverage from the ultraviolet to the infrared is desirable for heterodyne super-resolution imaging1, broadband infrared microscopy2, protein structure determination3 and standoff trace-gas detection4. To

Mid-infrared frequency combs at 10 GHz

June 29, 2020
Author(s)
Abijith S. Kowligy, David Carlson, Daniel D. Hickstein, Henry R. Timmers, Alexander Lind, Scott Papp, Scott Diddams
We demonstrate 10 GHz mid-infrared frequency combs spanning 3-5 μm and 7-11 μm that are generated with few-cycle electro-optic pulses and intrapulse difference-frequency generation.

All-fiber frequency comb at 2 mm providing 1.4-cycle pulses

May 1, 2020
Author(s)
Sida Xing, Abijith S. Kowligy, Daniel Lesko, Alexander Lind, Scott Diddams
We report an all-fiber approach to generating sub-2-cycle pulses at 2 µm and a corresponding octave-spanning optical frequency comb. Our configuration leverages mature erbium:fiber laser technology at 1.5 µm to provide a seed pulse for a thulium-doped

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

Self-organized nonlinear gratings for ultrafast nanophotonics

June 3, 2019
Author(s)
Daniel D. Hickstein, David R. Carlson, Haridas Mundoor, Jacob B. Khurgin, Kartik A. Srinivasan, Daron A. Westly, Abijith S. Kowligy, Ivan I. Smalyukh, Scott A. Diddams, Scott B. Papp
We present the first demonstration of automatically quasi-phase-matched second-harmonic generation using femtosecond pulses. The high-confinement geometry of silicon-nitride nanophotonic waveguides provides group-velocity matching, which enables efficient

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

Quasi-Phase-Matched Supercontinuum Generation in Photonic Waveguides

February 1, 2018
Author(s)
Daniel D. Hickstein, Grace Kerber, David R. Carlson, Lin Chang, Daron A. Westly, Kartik A. Srinivasan, Abijith S. Kowligy, John Bowers, Scott A. Diddams, Scott B. Papp
Supercontinuum generation in on-chip waveguides is a versatile source of broadband light and the generated spectrum is determined by the phase-matching conditions. Here we show that quasi- phase-matching via periodic modulations of the waveguide structure

High-harmonic generation in periodically poled waveguides

December 19, 2017
Author(s)
Daniel D. Hickstein, David R. Carlson, Abijith S. Kowligy, Matt Kirchner, Scott Domingue, Nima Nader, Henry R. Timmers, Alexander J. Lind, Gabriel G. Ycas, Margaret Murnane, Henry Kapteyn, Scott B. Papp, Scott A. Diddams
Optical waveguides made from periodically poled materials provide high confinement of light and enable the generation of new wavelengths via quasi-phase-matching, making them a key platform for nonlinear optics and photonics. However, such devices are not

Ultrabroadband Supercontinuum Generation and Frequency-Comb Stabilization Using On-Chip Waveguides with Both Cubic and Quadratic Nonlinearities

July 24, 2017
Author(s)
Daniel D. Hickstein, Hojoong Jung, David R. Carlson, Alexander J. Lind, Ian R. Coddington, Kartik A. Srinivasan, Gabriel G. Ycas, Daniel C. Cole, Abijith S. Kowligy, Stefan Droste, Erin S. Lamb, Nathan R. Newbury, Hong X. Tang, Scott A. Diddams, Scott B. Papp
Using aluminum-nitride photonic-chip waveguides, we generate optical frequency comb supercontinuum spanning 500~nm to 4000~nm, and show that the spectrum can be widely tailored by changing the geometry of the waveguide. Since aluminum nitride exhibits both