Novel local oscillator stabilization scheme for optical clocks

Alastair G. Sinclair, V. Letchumanan, Patrick Robert Gill +1 more

Controlled modulation of laser phase in an optical Ramsey experiment yields an antisymmetric lineshape. This discriminant is used to stabilize a local oscillator to the optical clock transition in a single 88Sr+ ion.

Michael Hohensee, David H. Phillips, Ronald Lee Walsworth

Robert Kimberk, Edward Tong, T. R. Hunter +2 more

V. Letchumanan, Patrick Robert Gill, Alastair G. Sinclair +1 more

Stabilization of a laser to an optical-clock transition has been demonstrated using Ramsey's phase-modulation technique. The technique was implemented using a 674 nm laser and a component of the 5 s 2S1/2 → 4d 2D5/2 optical clock transition in a single 88Sr+ ion. The lock performance observed was consistent with the short-term stability of the local oscillator. Compared with existing frequency-modulation stabilization schemes, this technique offers advantages for use in single-ion optical clocks through its possible increased resolution and the ability to conveniently compensate known systematic shifts.

Grant W. Biedermann, Ken Takase, Xiaojing Wu +3 more

We demonstrate a zero-dead-time operation of atomic clocks. This clock reduces sensitivity to local oscillator noise, integrating as nearly 1/τ whereas a clock with dead time integrates as 1/τ(1/2) under identical conditions. We contend that a similar scheme may be applied to improve the stability of optical clocks.

Christian Lisdat, Carsten Klempt