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JD Deschenes (IntlAssoc)


Low-Loss Reciprocal Optical Terminals for Two-Way Time-Frequency Transfer

William C. Swann, Laura C. Sinclair, Isaac H. Khader, Nathan R. Newbury, Jean-Daniel Deschenes, Hugo Bergeron
Optical two-way time-frequency transfer (O-TWTFT) over atmospheric free-space paths requires low- loss, single-mode, bi-directional and fully reciprocal optical

Femtosecond synchronization of optical clocks over free-space links

Jean-Daniel Deschenes, Laura C. Sinclair, Fabrizio R. Giorgetta, William C. Swann, Esther Baumann, Hugo Bergeron, Michael A. Cermak, Nathan R. Newbury
The use of optical clocks/oscillators in future ultra-precise navigation, gravitational sensing, and relativity experiments will require time comparison and

A compact optically coherent fiber frequency comb

Laura C. Sinclair, Jean-Daniel Deschenes, Lindsay I. Sonderhouse, William C. Swann, Isaac H. Khader, Esther Baumann, Nathan R. Newbury, Ian R. Coddington
We describe design and operation of a robust self-referenced, optically coherent frequency comb. The system robustness is derived from a combination of an

Patents (2018-Present)

Synchronizer And Synchronizing Transfer Over An Optical Link

NIST Inventors
Laura Sinclair , William C. Swann and JD Deschenes
A synchronizer for synchronizing transfer over an optical link includes a frequency reference oscillator; a tracking optical timing source; a tracking comb signal; a signal processor-controller; a comb timing discriminator; a clock frequency comb; a bidirectional terminal; a time-frequency offset
Powerpoint slide, showing via map and photograhpy, the distance from NIST Boulder to Valmont Butte

Optical Time Distributor and Process for Optical Two-Way Time-Frequency Transfer

NIST Inventors
Laura Sinclair , William C. Swann and JD Deschenes
An optical time distributor includes: a master clock including: a master comb; a transfer comb; and a free-space optical terminal; and a remote clock in optical communication with the master clock via a free space link and including: a remote comb that produces: a remote clock coherent optical pulse
Created October 1, 2019, Updated December 9, 2022