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Search Publications by: Scott Diddams (Assoc)

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Displaying 101 - 125 of 320

Demonstration of on-sky calibration of astronomical spectra using a 20 GHz near-IR laser frequency comb

March 6, 2012
Author(s)
Gabriel G. Ycas, Franklyn J. Quinlan, Scott A. Diddams, Steve Osterman, Chad F. Bender, Brandon Botzer, Lawrence W. Ramsey, Ryan Terrien, Suvrath Mahadevan, Stephen L. Redman
We describe and characterize a 25 GHz laser frequency comb based on a cavity-filtered erbium fiber mode-locked laser that provides a uniform array of optical frequencies stabilized using the GPS-system atomic clocks spanning 1475–1625 nm. This comb was

A High-Resolution Atlas of Uranium-Neon in the H Band

February 3, 2012
Author(s)
Scott A. Diddams, Stephen L. Redman, Gabriel G. Ycas, Ryan Terrien, Suvrath Mahadevan, Lawrence W. Ramsey, Chad F. Bender, Steve Osterman, Franklyn J. Quinlan, James E. Lawler, Gillian Nave
The rapid advance in near-infrared (NIR) detector technology in the past decade has lead to a number of high-resolution astronomical spectrometers that are either in operation or in the planning stages. Precision wavelength calibration techniques

Noise floor reduction of an Er:fiber laser-based photonic microwave generator

December 1, 2011
Author(s)
Haifeng (. Jiang, Jennifer A. Taylor, Franklyn J. Quinlan, Tara M. Fortier, Scott A. Diddams
Commercially available erbium-doped mode-locked fiber lasers are compact, robust, and suitable to be the frequency divider of an ultra-low phase noise photonic microwave generator. However, for a mode-locked fiber laser with repetition rate of a few

Mid-infrared upconversion spectroscopy based on a Yb:fiber frequency laser

October 11, 2011
Author(s)
Scott A. Diddams, Todd Johnson
We present a system for molecular spectroscopy using a mid-infrared broadband frequency comb source with near infrared detection. Difference frequency generation of a Yb:fiber frequency comb produced a mid-infrared (MIR) comb tunable from 2.7 − 4.7 υm

Ultralow phase noise microwave generation with an Er:fiber-based optical frequency divider

August 15, 2011
Author(s)
Franklyn J. Quinlan, Tara M. Fortier, Matthew S. Kirchner, Jennifer A. Taylor, Michael J. Thorpe, Nathan D. Lemke, Andrew D. Ludlow, Yanyi Jiang, Christopher W. Oates, Scott A. Diddams
We present an optical frequency divider based on a 200 MHz repetition rate Er:fiber mode-locked laser that, when locked to a stable optical frequency reference, generates microwave signals with absolute phase noise that is equal to or better than cryogenic

Generation of Ultrastable microwaves via optical frequency division

June 26, 2011
Author(s)
Tara Fortier, Matthew S. Kirchner, Jennifer A. Taylor, James C. Bergquist, Yanyi Jiang, Andrew Ludlow, Christopher W. Oates, Till P. Rosenband, Scott Diddams, Franklyn Quinlan, Nathan D. Lemke
A frequency-stabilized femtosecond laser optical frequency comb serves as a source of microwave signals having very low close-to-carrier phase noise. Comparison of two independent systems shows combined absolute phase noise of -100 dBc/Hz at an offset of 1

The Impact of Dispersion on Amplitude and Frequency Noise in a Yb-fiber Laser Comb

May 1, 2011
Author(s)
Lora L. Nugent-Glandorf, Todd Johnson, Yohei Kobayashi, Scott A. Diddams
We describe a Yb-fiber based laser comb, with a focus on the relationship between net cavity dispersion and the amplitude noise and frequency noise on the comb. While tuning the net cavity dispersion from anomalous to normal, we measure the amplitude noise

Microresonator based optical frequency combs

April 29, 2011
Author(s)
Scott A. Diddams, T. J. Klippenberg
Optical frequency combs based on mode-locked laser sources have provided unprecedented measurement capabilities for optical frequencies, enabling new applications in a wide range of topics that include atomic clocks, ultracold gases, molecular

Characterization of Power-to-Phase Conversion in High-Speed P-I-N Photodiodes

February 1, 2011
Author(s)
Jennifer A. Taylor, Shubahshish Datta, Archita Hati, Craig W. Nelson, Franklyn J. Quinlan, Abhay Joshi, Scott A. Diddams
Fluctuations of the optical power incident on a photodiode can be converted into phase fluctuations of the resulting electronic signal due to nonlinear saturation in the semiconductor. This impacts overall timing stability (phase noise) of microwave

An optical frequency comb for infrared spectrograph calibration

November 17, 2010
Author(s)
Gabriel G. Ycas, Franklyn J. Quinlan, Steve Osterman, Gillian Nave, Craig J. Sansonetti, Scott A. Diddams
Detection of extrasolar planets by measurement of the stellar radial velocity shift requires high resolution spectroscopy with long term stability. Presently, the primary wavelength standards in the NIR are NePt and ThAr lamps and absorption cells. These

The evolving optical frequency comb

October 22, 2010
Author(s)
Scott A. Diddams
Much as natural historians search for the first roots of our human race, curiosity drives the laser scientist to pursue the roots of his or her own field. This is especially the case in this year where our community celebrates the 50th anniversary of the

Phase Noise in the Photodetection of Ultrashort Optcial Pulses

June 2, 2010
Author(s)
Jennifer A. Taylor, Franklyn J. Quinlan, Archita Hati, Craig W. Nelson, Scott A. Diddams, Shubahshish Datta, Abhay Joshi
Femtosecond laser frequency combs provide an effective and efficient way to take an ultra-stable optical frequency reference and divide the signal down into the microwave region. In order to convert optical pulses into a usable rf signal, one must use high

Mid-IR frequency comb upconversion spectroscopy

May 16, 2010
Author(s)
Todd Johnson, Scott A. Diddams
We present a mid-infrared frequency comb generated via differency frequency mixing of a Yb femtosecond fiber laser. After passing through a methane gas sample, the MIR comb is upconverted and dispersed onto a CCD for detection.

Optical frequency stabilization of a 10 GHz Ti:sapphire frequency comb by saturated absorption spectroscopy in 87Rubidium

November 4, 2009
Author(s)
Dirk Heinecke, Albrecht Bartels, Tara M. Fortier, Danielle Braje, Leo Hollberg, Scott A. Diddams
The high power per mode of a recently-developed 10 GHz femtosecond Ti:sapphire frequency comb permits nonlinear Doppler-free saturation spectroscopy in 87Rubidium with a single mode of the comb. We use this access to the natural linewidth of the Rubidium

10-GHz Self-Referenced Optical Frequency Comb

October 30, 2009
Author(s)
Albrecht Bartels, Dirk Heinecke, Scott Diddams
For a decade the femtosecond laser based frequency comb has played a key role in high precision optical frequency metrology.While often referred to as a precise optical frequency ruler, its tick marks are in fact too densely spaced for direct observation

A Spin-1/2 Optical Lattice Clock

August 7, 2009
Author(s)
Nathan D. Lemke, Andrew D. Ludlow, Zeb Barber, Tara M. Fortier, Scott A. Diddams, Yanyi Jiang, Steven R. Jefferts, Thomas P. Heavner, Thomas E. Parker, Christopher W. Oates
We experimentally investigate an optical clock based on 171Yb (I = 1/2) atoms confined in an optical lattice. We have evaluated all known frequency shifts to the clock transition, including the density-dependent collision shift, with an uncertainty of 0.19

Frequency Measurements of Al+ and Hg+ Optical Standards

June 8, 2009
Author(s)
Wayne M. Itano, James C. Bergquist, Till P. Rosenband, David J. Wineland, David Hume, Chin-wen Chou, Steven R. Jefferts, Thomas P. Heavner, Tom Parker, Scott Diddams, Tara Fortier
Frequency standards based on narrow optical transitions in 27Al+ and 199Hg+ ions have been developed at NIST. Both standards have absolute reproducibilities of a few parts in 10 17. This is about an order of magnitude better than the fractional uncertainty

A deep-UV optical frequency comb at 205 nm

May 25, 2009
Author(s)
Scott A. Diddams, E Peters, P Fendel, S Reinhardt, T W. Hansch, T Udem
By frequency quadrupling a picosecond pulse train from a Ti:sapphire laser at 820 nm we generate a frequency comb at 205 nm with nearly bandwidth-limited pulses. The nonlinear frequency conversion is accomplished by two successive frequency doubling stages