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Title: Fractional frequency instability in the 10{sup -14} range with a thermal beam optical frequency reference

Abstract

We demonstrate a means of increasing the signal-to-noise ratio in a Ramsey-Borde interferometer with spatially separated oscillatory fields on a thermal atomic beam. The {sup 1}S{sub 0}{r_reversible}{sup 3}P{sub 1} intercombination line in neutral {sup 40}Ca is used as a frequency discriminator, with an extended cavity diode laser at 423 nm probing the ground state population after a Ramsey-Borde sequence of 657 nm light-field interactions with the atoms. Evaluation of the instability of the Ca frequency reference is carried out by comparison with (i) a hydrogen-maser and (ii) a cryogenic sapphire oscillator. In the latter case the Ca reference exhibits a square-root {Lambda} variance of 9.2x10{sup -14} at 1 s and 2.0x10{sup -14} at 64 s. This is an order-of-magnitude improvement for optical beam frequency references, to our knowledge. The shot noise of the readout fluorescence produces a limiting square-root {Lambda} variance of 7x10{sup -14}/{radical}({tau}), highlighting the potential for improvement. This work demonstrates the feasibility of a portable frequency reference in the optical domain with 10{sup -14} range frequency instability.

Authors:
;  [1]
  1. School of Physics, University of Western Australia, 35 Stirling Highway, Crawley 6009, W.A. (Australia)
Publication Date:
OSTI Identifier:
22046838
Resource Type:
Journal Article
Journal Name:
Journal of the Optical Society of America. Part B, Optical Physics
Additional Journal Information:
Journal Volume: 27; Journal Issue: 2; Other Information: (c) 2010 Optical Society of America; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0740-3224
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; ATOMIC BEAMS; CALCIUM 40; COMPARATIVE EVALUATIONS; FLUORESCENCE; GROUND STATES; HYDROGEN; INSTABILITY; INTERFEROMETERS; LASER CAVITIES; MASERS; NOISE; OSCILLATORS; PHOTON-ATOM COLLISIONS; READOUT SYSTEMS; RESONATORS; SAPPHIRE; SEMICONDUCTOR LASERS; SIGNAL-TO-NOISE RATIO; VISIBLE RADIATION

Citation Formats

McFerran, John J, and Luiten, Andre N. Fractional frequency instability in the 10{sup -14} range with a thermal beam optical frequency reference. United States: N. p., 2010. Web. doi:10.1364/JOSAB.27.000277.
McFerran, John J, & Luiten, Andre N. Fractional frequency instability in the 10{sup -14} range with a thermal beam optical frequency reference. United States. https://doi.org/10.1364/JOSAB.27.000277
McFerran, John J, and Luiten, Andre N. 2010. "Fractional frequency instability in the 10{sup -14} range with a thermal beam optical frequency reference". United States. https://doi.org/10.1364/JOSAB.27.000277.
@article{osti_22046838,
title = {Fractional frequency instability in the 10{sup -14} range with a thermal beam optical frequency reference},
author = {McFerran, John J and Luiten, Andre N},
abstractNote = {We demonstrate a means of increasing the signal-to-noise ratio in a Ramsey-Borde interferometer with spatially separated oscillatory fields on a thermal atomic beam. The {sup 1}S{sub 0}{r_reversible}{sup 3}P{sub 1} intercombination line in neutral {sup 40}Ca is used as a frequency discriminator, with an extended cavity diode laser at 423 nm probing the ground state population after a Ramsey-Borde sequence of 657 nm light-field interactions with the atoms. Evaluation of the instability of the Ca frequency reference is carried out by comparison with (i) a hydrogen-maser and (ii) a cryogenic sapphire oscillator. In the latter case the Ca reference exhibits a square-root {Lambda} variance of 9.2x10{sup -14} at 1 s and 2.0x10{sup -14} at 64 s. This is an order-of-magnitude improvement for optical beam frequency references, to our knowledge. The shot noise of the readout fluorescence produces a limiting square-root {Lambda} variance of 7x10{sup -14}/{radical}({tau}), highlighting the potential for improvement. This work demonstrates the feasibility of a portable frequency reference in the optical domain with 10{sup -14} range frequency instability.},
doi = {10.1364/JOSAB.27.000277},
url = {https://www.osti.gov/biblio/22046838}, journal = {Journal of the Optical Society of America. Part B, Optical Physics},
issn = {0740-3224},
number = 2,
volume = 27,
place = {United States},
year = {Mon Feb 15 00:00:00 EST 2010},
month = {Mon Feb 15 00:00:00 EST 2010}
}