https://doi.org/10.1140/epjqt/s40507-020-0078-7
Research
Sensing microwave photons with a Bose–Einstein condensate
Department of Quantum Optics and Quantum Information, Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, Budapest, Hungary
* e-mail: kalman.orsolya@wigner.mta.hu
Received:
30
November
2018
Accepted:
8
January
2020
Published online:
15
January
2020
We consider the interaction of a magnetically trapped Bose–Einstein condensate of Rubidium atoms with the stationary microwave radiation field sustained by a coplanar waveguide resonator. This coupling allows for the measurement of the magnetic field of the resonator by means of counting the atoms that fall out of the condensate due to hyperfine transitions to non-trapped states. We determine the quantum efficiency of this detection scheme and show that weak microwave fields at the single-photon level can be sensed.
Key words: Bose–Einstein condensate / Waveguide resonator / Magnetic field sensing / Hyperfine transition / Atomlaser
© The Author(s), 2020