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Title: Long-term frequency instability of atomic frequency references based on coherent population trapping and microfabricated vapor cells

Abstract

We present an evaluation of the long-term frequency instability and environmental sensitivity of a chip-scale atomic clock based on coherent population trapping, particularly as affected by the light-source subassembly. The long-term frequency stability of this type of device can be dramatically improved by judicious choice of operating parameters of the light-source subassembly. We find that the clock frequency is influenced by the laser-injection current, the laser temperature, and the rf modulation index. The sensitivity of the clock frequency to changes in the laser-injection current or the substrate temperature can be significantly reduced through adjustment of the rf modulation index. This makes the requirements imposed on the laser-temperature stabilization, in order to achieve a given frequency stability, less severe. The clock-frequency instability due to variations in local oscillator power is shown to be reduced through the choice of an appropriate light intensity inside the cell. The importance of these parameters with regard to the long-term stability of such systems is discussed.

Authors:
; ; ; ; ;  [1];  [2];  [2];  [2]
  1. Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556 (United States)
  2. (United States)
Publication Date:
OSTI Identifier:
20768749
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of the Optical Society of America. Part B, Optical Physics; Journal Volume: 23; Journal Issue: 4; Other Information: DOI: 10.1364/JOSAB.23.000593; (c) 2006 Optical Society of America; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ATOMIC CLOCKS; BEAM INJECTION; EVALUATION; INSTABILITY; LASERS; LIGHT SOURCES; MODULATION; OSCILLATORS; RADIATION PRESSURE; SENSITIVITY; STABILIZATION; SUBSTRATES; TRAPPING

Citation Formats

Gerginov, Vladislav, Knappe, Svenja, Shah, Vishal, Schwindt, Peter D. D., Hollberg, Leo, Kitching, John, Department of Physics, University of Colorado, Boulder, Colorado 80309, Time and Frequency Division, National Institute of Standards and Technology, 325 Broadway M.S. 847, Boulder, Colorado 80305, and Time and Frequency Division, National Institute of Standards and Technology, 325 Broadway M.S. 847, Boulder Colorado 80305. Long-term frequency instability of atomic frequency references based on coherent population trapping and microfabricated vapor cells. United States: N. p., 2006. Web. doi:10.1364/JOSAB.23.000593.
Gerginov, Vladislav, Knappe, Svenja, Shah, Vishal, Schwindt, Peter D. D., Hollberg, Leo, Kitching, John, Department of Physics, University of Colorado, Boulder, Colorado 80309, Time and Frequency Division, National Institute of Standards and Technology, 325 Broadway M.S. 847, Boulder, Colorado 80305, & Time and Frequency Division, National Institute of Standards and Technology, 325 Broadway M.S. 847, Boulder Colorado 80305. Long-term frequency instability of atomic frequency references based on coherent population trapping and microfabricated vapor cells. United States. doi:10.1364/JOSAB.23.000593.
Gerginov, Vladislav, Knappe, Svenja, Shah, Vishal, Schwindt, Peter D. D., Hollberg, Leo, Kitching, John, Department of Physics, University of Colorado, Boulder, Colorado 80309, Time and Frequency Division, National Institute of Standards and Technology, 325 Broadway M.S. 847, Boulder, Colorado 80305, and Time and Frequency Division, National Institute of Standards and Technology, 325 Broadway M.S. 847, Boulder Colorado 80305. Sat . "Long-term frequency instability of atomic frequency references based on coherent population trapping and microfabricated vapor cells". United States. doi:10.1364/JOSAB.23.000593.
@article{osti_20768749,
title = {Long-term frequency instability of atomic frequency references based on coherent population trapping and microfabricated vapor cells},
author = {Gerginov, Vladislav and Knappe, Svenja and Shah, Vishal and Schwindt, Peter D. D. and Hollberg, Leo and Kitching, John and Department of Physics, University of Colorado, Boulder, Colorado 80309 and Time and Frequency Division, National Institute of Standards and Technology, 325 Broadway M.S. 847, Boulder, Colorado 80305 and Time and Frequency Division, National Institute of Standards and Technology, 325 Broadway M.S. 847, Boulder Colorado 80305},
abstractNote = {We present an evaluation of the long-term frequency instability and environmental sensitivity of a chip-scale atomic clock based on coherent population trapping, particularly as affected by the light-source subassembly. The long-term frequency stability of this type of device can be dramatically improved by judicious choice of operating parameters of the light-source subassembly. We find that the clock frequency is influenced by the laser-injection current, the laser temperature, and the rf modulation index. The sensitivity of the clock frequency to changes in the laser-injection current or the substrate temperature can be significantly reduced through adjustment of the rf modulation index. This makes the requirements imposed on the laser-temperature stabilization, in order to achieve a given frequency stability, less severe. The clock-frequency instability due to variations in local oscillator power is shown to be reduced through the choice of an appropriate light intensity inside the cell. The importance of these parameters with regard to the long-term stability of such systems is discussed.},
doi = {10.1364/JOSAB.23.000593},
journal = {Journal of the Optical Society of America. Part B, Optical Physics},
number = 4,
volume = 23,
place = {United States},
year = {Sat Apr 15 00:00:00 EDT 2006},
month = {Sat Apr 15 00:00:00 EDT 2006}
}
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