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Search Publications by: Alexander Lind (Assoc)

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Displaying 1 - 18 of 18

Dual-comb correlation spectroscopy of thermal light

May 23, 2024
Author(s)
Eugene Tsao, Alexander Lind, Connor Fredrick, Ryan Cole, Peter Chang, Kristina Chang, Dahyeon Lee, Matthew Heyrich, Nazanin Hoghooghi, Franklyn Quinlan, Scott Diddams
The detection of light of thermal origin is the principal means by which humanity has learned about our world and the cosmos. In optical astronomy, in particular, direct detection of thermal photons and the resolution of their spectra have enabled

Multi-harmonic near-infrared-ultraviolet dual-comb spectrometer

March 19, 2024
Author(s)
Kristina Chang, Daniel Lesko, Carter Mashburn, Peter Chang, Eugene Tsao, Alexander Lind, Scott Diddams
Dual-comb spectroscopy in the ultraviolet (UV) and visible would enable broad bandwidth electronic spectroscopy with unprecedented frequency resolution. However, there are significant challenges in generation, detection, and processing of dual-comb data

1-GHz mid-infrared frequency comb spanning 3 to 13 mm

January 18, 2022
Author(s)
Nazanin Hoghooghi, Sida XIng, Peter Chang, Daniel Lesko, Alexander Lind, Greg Rieker, Scott Diddams
Mid-infrared (MIR) spectrometers are invaluable tools for molecular fingerprinting and imaging. Among the available spectroscopic approaches, MIR dual-comb absorption spectrometers have the potential to simultaneously combine the high-speed, high spectral

Single-cycle all-fiber frequency comb

July 8, 2021
Author(s)
Sida Xing, Daniel Lesko, Takeshi Umeki, Tsung Han Wu, Alexander Lind, Nazanin Hoghooghi, Scott Diddams
Broad bandwidth mid-infrared frequency combs are important for molecular spectroscopy in a wide range of fundamental and applied research. However, realization of such light sources in a compact and robust format remains a challenge. In this paper, we

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

Mid-Infrared Frequency Comb Generation and Spectroscopy with Few-Cycle Pulses and hd2TH Nonlinear Optics

April 1, 2020
Author(s)
Alexander Lind, Abijith S. Kowligy, Henry R. Timmers, Flavio Caldas da Cruz, Nima Nader, Myles C. Silfies, Thomas K. Allison, Scott Papp, Scott Diddams
The mid-infrared atmospheric window of 3–5.5 μm holds valuable information regarding molecular composition and function for fundamental and applied spectroscopy. Using a robust, mode-locked fiberlaser source of 11 fs pulses in the near infrared, we

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 ( 2 dB) and broadband 3 dB output coupling spanning 6.0-8.5 υm

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

Tunable mid-infrared generation via wide-band four-wave mixing in silicon nitride waveguides

August 27, 2018
Author(s)
Abijith S. Kowligy, Daniel D. Hickstein, Alexander Lind, David Carlson, Henry R. Timmers, Nima Nader, Daniel Maser, Daron Westly, Kartik Srinivasan, Scott Papp, Scott Diddams
We demonstrate wide-band frequency down-conversion to the mid-infrared (MIR) using four-wave mixing (FWM) of near-infrared (NIR) femtosecond-duration pulses from an Er:fiber laser, corresponding to 100 THz spectral translation. Photonic-chip-based silicon

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

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

Photonic-Chip Supercontinuum with Tailored Spectra for Counting Optical Frequencies

July 24, 2017
Author(s)
David R. Carlson, Daniel D. Hickstein, Alexander J. Lind, Judith B. Olson, Richard W. Fox, Roger C. Brown, Andrew D. Ludlow, Qing Li, Daron A. Westly, Tara M. Fortier, Kartik A. Srinivasan, Scott A. Diddams, Scott B. Papp
Supercontinuum generation using chip-integrated photonic waveguides is a powerful approach for spectrally broadening pulsed laser sources with very low pulse energies and compact form factors. When pumped with a mode-locked laser frequency comb, these

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

Self-referenced frequency combs using high-efficiency silicon nitride waveguides

June 12, 2017
Author(s)
David R. Carlson, Daniel D. Hickstein, Alexander J. Lind, Stefan Droste, Daron A. Westly, Nima Nader, Ian R. Coddington, Nathan R. Newbury, Kartik A. Srinivasan, Scott A. Diddams, Scott B. Papp
We utilize silicon nitride waveguides to self-reference telecom-wavelength fiber frequency combs through supercontinuum generation using less than 15 mW total optical average power. This is approximately ten times lower than conventional approaches using