US 7,468,637 B2
Batch-fabricated, RF-interrogated, end transition, chip-scale atomic clock
Alan Michael Braun, Lawrenceville, N.J. (US); Joseph Hy Abeles, East Brunswick, N.J. (US); Winston Kong Chan, Princeton, N.J. (US); Martin Kwakernaak, New Brunswick, N.J. (US); and Timothy James Davis, Columbus, N.J. (US)
Assigned to Sarnoff Corporation, Princeton, N.J. (US)
Filed on Apr. 18, 2007, as Appl. No. 11/736,657.
Claims priority of provisional application 60/793171, filed on Apr. 19, 2006.
Prior Publication US 2007/0247241 A1, Oct. 25, 2007
Int. Cl. H01S 1/06 (2006.01); H03L 7/26 (2006.01)
U.S. Cl. 331—94.1  [331/3] 33 Claims
OG exemplary drawing
 
1. An atomic clock, comprising:
an alkali vapor cell containing alkali atoms;
a laser source in optical communication with said alkali vapor cell for pumping an optical signal through said alkali atoms, said alkali atoms being excited into an end resonance state;
a photodetector in optical communication with said alkali vapor cell and configured to detect the optical signal, wherein said laser source, said alkali vapor cell, and said photodetector are aligned along a first axis;
a pair of RF excitation coils for applying an RF-interrogation signal having a wavelength that is larger than the dimensions of said alkali vapor cell to said alkali atoms substantially along a second axis perpendicular to said first axis through said alkali vapor cell, each of said pair of RF excitation coils being proximal to and physically isolated from said alkali vapor cell;
a pair of bias coils for applying a substantially uniform DC magnetic field along said first axis through said alkali vapor cell, each of said pair of bias coils being located external to and physically and thermally isolated from said alkali vapor cell; and
a pair of Zeeman coils for applying a Zeeman interrogation signal to said alkali atoms and oriented and configured to apply a time-varying magnetic field along said second axis through said alkali vapor cell, each of said pair of Zeeman coils being located external to and physically and thermally isolated from said alkali vapor cell.