Search Results - "Tjoelker, Robert L."

Using the Deep Space Atomic Clock for Navigation and Science by Ely, Todd A., Burt, Eric A., Prestage, John D., Seubert, Jill M., Tjoelker, Robert L.

“…Routine use of one-way radiometric tracking for deep space navigation and radio science is not possible today because spacecraft frequency and time references…”
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Ultra-Stable RF-Over-Fiber Transport in NASA Antennas, Phased Arrays and Radars by Lau, Kam Y., Lutes, George F., Tjoelker, Robert L.

“…Research and development in ultra-stable RF transport in optical fibers in the late-1970s/early-1980s at the NASA Jet Propulsion Laboratory led to successful…”
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Mercury Ion Clock for a NASA Technology Demonstration Mission by Tjoelker, Robert L., Prestage, John D., Burt, Eric A., Pin Chen, Chong, Yong J., Chung, Sang K., Diener, William, Ely, Todd, Enzer, Daphna G., Mojaradi, Hadi, Okino, Clay, Pauken, Mike, Robison, David, Swenson, Bradford L., Tucker, Blake, Wang, Rabi

“…There are many different atomic frequency standard technologies but only few meet the demanding performance, reliability, size, mass, and power constraints…”
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Integrated physics package of micromercury trapped ion clock with 10 − 14-level frequency stability by Hoang, Thai M., Chung, Sang K., Le, Thanh, Prestage, John D., Yi, Lin, Tjoelker, Robert L., Park, Sehyun, Park, Sung-Jin, Eden, J. Gary, Holland, Christopher, Yu, Nan

“…Mercury trapped ion clocks have demonstrated great long-term frequency stability and robustness. In this paper, we report a demonstration of an integrated…”
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JPL Ultrastable Trapped Ion Atomic Frequency Standards by Burt, Eric A., Lin Yi, Tucker, Blake, Hamell, Robert, Tjoelker, Robert L.

“…Recently, room temperature trapped ion atomic clock development at the Jet Propulsion Laboratory (JPL) has focused on three directions: 1) ultrastable atomic…”
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Drifts and Environmental Disturbances in Atomic Clock Subsystems: Quantifying Local Oscillator, Control Loop, and Ion Resonance Interactions by Enzer, Daphna G., Diener, William A., Murphy, David W., Rao, Shanti R., Tjoelker, Robert L.

“…Linear ion trap frequency standards are among the most stable continuously operating frequency references and clocks. Depending on the application, they have…”
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Stability Demonstration of a 15-cc Mercury-Ion Vacuum Trap Tube by Hoang, Thai M., Chung, Sang K., Le, Thanh, Prestage, John D., Yi, Lin, Tjoelker, Robert L., Yu, Nan

“…In this paper, we report our recent effort on developing a micro mercury trapped ion atomic clock. In particular, we present preliminary results of a…”
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A compensated multi-pole linear ion trap mercury frequency standard for ultra-stable timekeeping by Burt, E.A., Diener, W.A., Tjoelker, R.L.

“…The multi-pole linear ion trap frequency standard (LITS) being developed at the Jet Propulsion Laboratory (JPL) has demonstrated excellent short- and long-term…”
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Atomic Clocks and Variations of the FIne Structure Constant by Prestage, John D., Tjoelker, Robert L., Maleki, Lute

“…We describe a new test for possible variations of the fine structure constant alpha by comparisons of rates between clocks based on hyperfine transitions in…”
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Demonstration of a Mercury Trapped Ion Clock Prototype by Hoang, Thai M., Chung, Sang K., Le, Thanh, Prestage, John D., Yi, Lin, Tjoelker, Robert L., Yu, Nan, Park, Sehyun, Park, Sung-Jin, Eden, J. Gary, Holland, Christopher

“…In this work, we report a prototype of micro mercury trapped ion atomic clock. All the clock components have been packaged and demonstrated in a magnetic…”
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Stable Photonic Links for Frequency and Time Transfer in the Deep-Space Network and Antenna Arrays by Calhoun, Malcolm, Huang, Shouhua, Tjoelker, Robert L.

“…For more than two decades, NASA deep space network (DSN) frequency and timing metrology has been a driving application for remote transfer of stable…”
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A new trapped ion atomic clock based on super(201)Hg by Burt, Eric A, Taghavi-Larigani, Shervin, Tjoelker, Robert L

“…High-resolution spectroscopy has been performed on the ground-state hyperfine transitions in trapped super(201)Hg+ ions as part of a program to investigate the…”
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Stable Photonic Links for Frequency and Time Transfer in the Deep-Space Network and Antenna Arrays: Technical advances in deep space communications & tracking: Part 1 by CALHOUN, Malcolm, HUANG, Shouhua, TJOELKER, Robert L

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A new trapped ion atomic clock based on 201Hg by Burt, E.A., Taghavi-Larigani, S., Tjoelker, R.L.

“…High-resolution spectroscopy has been performed on the ground-state hyperfine transitions in trapped 201 Hg + ions as part of a program to investigate the…”
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A Low SWaP-C Prototype Ka-Band Frequency Synthesizer for Atomic Clocks by Toennies, Michael O., Yi, Lin, Burt, Eric A., Tjoelker, Robert L.

“…We present a low size, weight, power and cost (SWaP-C) prototype circuit of a Ka-band frequency synthesizer. It takes advantage of a phase-locked loop single…”
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Miniature Sapphire Acoustic Resonator (MSAR) by Wang, R.T., Dick, G.J., Tjoelker, R.L.

“…We present recent progress towards a Miniature Sapphire Acoustic Resonator (MSAR). Our goal is to develop an ultra-stable oscillator with a high Q room…”
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Design and progress report for compact cryocooled sapphire oscillator "VCSO" by Dick, G.J., Wang, R.T., Tjoelker, R.L.

“…We report on the development of a compact cryocooled sapphire oscillator "VCSO", designed for operational frequency and timing systems or metrology…”
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Probing magnetic field effects in 12-pole linear ion trap frequency standards by Burt, E.A., Prestage, J.D., Tjoelker, R.L.

“…The second-order Zeeman shift in a 12-pole buffer-gas-cooled linear ion trap frequency standard is characterized. Results for magnetic shielding effectiveness…”
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Doppler sideband spectra for ions in a linear trap by Prestage, J.D., Tjoelker, R.L., Dick, G.J., Maleki, L.

“…The authors describe a spectroscopic measurement of the temperature and linear density of Hg/sup +/ ions held in a linear ion trap (LIT). The inferred…”
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Improved linear ion trap physics package by Prestage, J.D., Tjoelker, R.L., Dick, G.J., Maleki, L.

“…The authors describes an improvement in the architecture of the physics package used in the linear ion trap (LIT) based frequency standard developed at the Jet…”
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