Relativistic Calculations of Atomic Clock

B. K. Sahoo

Marianna S. Safronova, Dansha Jiang, M. G. Kozlov +1 more

We developed a theoretical method within the framework of relativistic many-body theory to accurately treat correlation corrections in atoms with few valence electrons. Preliminary results for systems of interest to atomic clock development are reported. We also calculated the blackbody radiation shift of the ground-state hyperfine microwave transition in87Rb using the relativistic all-order method and evaluated the accuracy of our final value. The uncertainty estimate is discussed in detail.

Maximilian P. E. Lock, Ivette Fuentes

Vyacheslav F. Fateev, Fedor R. Smirnov, Карауш Артем Андреевич

Amar C. Vutha, Tom Kirchner, P. Dubé

Collisions with background gas particles can shift the resonance frequencies of atoms in atomic clocks. The internal quantum states of atoms can also become entangled with their motional states due to the recoil imparted by a collision, which leads to a further shift of the clock frequency through the relativistic Doppler shift. It can be complicated to evaluate the Doppler and collisional frequency shifts for clock atoms in such entangled states, but estimates of these shifts are essential in order to improve the accuracy of optical atomic clocks. We present a formalism that describes collisions and relativistic Doppler shifts in a unified manner, and can therefore be used to accurately estimate collisional frequency shifts in trapped-atom clocks.

Yanglin Hu, Maximilian P. E. Lock, Mischa P. Woods

Abstract We derive the predicted time dilation of delocalized atomic clocks in an optical lattice setup in the presence of a gravitational field to leading order in quantum relativistic corrections. We investigate exotic quantum states of motion whose relativistic time dilation is outside of the realm of classical general relativity, finding a regime where 24 Mg optical lattice clocks currently in development would comfortably be able to detect the special-relativistic contribution to the quantum effect (if the technical challenge of generating the necessary states can be met and the expected accuracy of such clocks can be attained). We find that the gravitational contribution, on the other hand, is negligible in this setup. We provide a detailed experimental protocol and analyse the effects of noise on our predictions. We also show that the magnitude of our predicted quantum time dilation effect remains just out of detectable reach for the current generation of 87 Sr optical lattice clocks. Our calculations agree with the predicted time dilation of classical general relativity when restricting to Gaussian states.