Hybrid quantum devices, incorporating both atoms and photons, are able to exploit the benefits of both systems. Compact, robust atom-photon interfaces will enable scalable architectures for quantum computing and quantum communication, as well as chip-scale sensors and single-photon sources. We demonstrate a new type of interface and show the interaction of cold cesium atoms with resonant photons. For this atoms are cooled in a magneto-optical trap, transferred to an optical dipole trap and positioned inside a transverse, 30 µm diameter through-hole in an optical fibre, created via laser micromachining. The intersection is orthogonal to the propagation direction of the light mode. We trap about 300 atoms at a temperature of 120µK. When the guided light is on resonance with the caesium D2 line, up to 87% of it is absorbed by the atoms. Our technique can be applied in 2-dimensional systems, i.e. in optical waveguide chips and other existing photonic systems. We also discuss the influence of hole shapes on transmission and prospects of adding a micro-cavity.
|