The integration of hollow anti-resonant reflecting optical waveguides (ARROWs) with vapor cells on silicon chips
provides a compact platform for a number of optical applications, including the study of quantum coherence effects such
as electromagnetically induced transparency and single-photon nonlinearities, as well as frequency stabilization
standards. The use of hollow waveguides allows for light propagation in low index (vapor) media with compact mode
areas. ARROWs make particularly attractive waveguides for this purpose because they can be interfaced with solid core
waveguides, microfabricated on a planar substrate, and are effectively single mode. ARROW fabrication utilizes an acidremoved
sacrificial core surrounded by alternating plasma deposited dielectric layers, which act as Fabry-Perot
reflectors. A demonstration platform consisting of solid and hollow core waveguides integrated with rubidium vapor
cells has been constructed. Rubidium was used because it is of particular interest for studying quantum coherence
effects. Liquefied rubidium was transferred from a bulk supply into an on-chip vapor cell in an anaerobic atmosphere
glovebox. Optical absorption measurements confirmed the presence of rubidium vapor within the hollow waveguide
platform. Coherence dephasing in the small dimensions of the ARROW (quantum coherence effect) can be addressed by
adding a buffer gas and passivation coatings to the ARROW walls.
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