Large Momentum Transfer Clock Atom Interferometry on the 689 nm Intercombination Line of Strontium

Abstract

We report the first realization of large momentum transfer (LMT) clock atom interferometry. Using single-photon interactions on the strontium 1 S0 -3 P1 transition, we demonstrate Mach-Zehnder interferometers with state-of-the-art momentum separation of up to 141 k and gradiometers of up to 81 k. Moreover, we circumvent excited state decay limitations and extend the gradiometer duration to 50 times the excited state lifetime. Due to the broad velocity acceptance of the interferometry pulses, all experiments are performed with laser-cooled atoms at a temperature of 3 µK. This work has applications in high-precision inertial sensing and paves the way for LMT-enhanced clock atom interferometry in gravitational wave detection and dark matter search proposals. arXiv:1910.05459v1 [physics.atom-ph]

AEDGE: Atomic Experiment for Dark Matter and Gravity Exploration in Space

“…Using resonant enhancement while reducing LMT allows the interferometer region to remain small, but it has an impact on the achievable sensitivity when setup is operated in broadband mode. In this context, we would like to point out that a strontiumbased single-photon atom interferometer has recently demonstrated 141 k LMT [84]. Although the demonstrated LMT does not yet reach the performance requirements for proposed ground-based detectors or AEDGE, it serves as a proof-of-principle for future LMT-enhanced clock atom interferometry for dark matter searches and gravitational wave detection.…”

High-accuracy inertial measurements with cold-atom sensors

“…Potassium for tests of the Weak Equivalence Principle), alkaline-earth atoms such as Sr 213 , or alkaline-earth-like atoms such as Yb 214 . The latter offer, for their bosonic isotopes having zero spin in the ground state, reduced sensitivity to stray magnetic fields, and a richer electronic structure, with narrow lines that can be used to implement single photon beamsplitters 215,216 or to implement quantum metrology measurement protocols, such as based on spinsqueezing 217-219 .…”

Multi-loop atomic Sagnac interferometry

“…Multiple experiments investigated beam splitting as well as relaunch operations as required for our scheme. They realised the transfer of large momenta with subsequent pulses or higher order transitions 32 – 37 and their combination with Bloch oscillations 30 , 38 , 39 . The implementation of symmetric splitting 40 – 44 was demonstrated with an effective wave number corresponding to 408 photon recoils in a twin-lattice atom interferometer 41 .…”