2020/05/02 by Jeffrey Holzgrafe, Holzgrafe, Jeffrey, Neil Sinclair +15 · 11 citations
Physics and Astronomy · #Mechanical and Optical Resonators #Advanced Fiber Laser Technologies #Photorefractive and Nonlinear Optics
paper · pdf · doi:10.48550/arxiv.2005.00939
Linking superconducting quantum devices to optical fibers via\nmicrowave-optical quantum transducers may enable large scale quantum networks.\nFor this application, transducers based on the Pockels electro-optic (EO)\neffect are promising for their direct conversion mechanism, high bandwidth, and\npotential for low-noise operation. However, previously demonstrated EO\ntransducers require large optical pump power to overcome weak EO coupling and\nreach high efficiency. Here, we create an EO transducer in thin-film lithium\nniobate, leveraging the low optical loss and strong EO coupling in this\nplatform. We demonstrate a transduction efficiency of up to 2.7\×10-5,\nand a pump-power normalized efficiency of 1.9\×10-6/ μ W.\nThe transduction efficiency can be improved by further reducing the microwave\nresonator's piezoelectric coupling to acoustic modes, increasing the optical\nresonator quality factor to previously demonstrated levels, and changing the\nelectrode geometry for enhanced EO coupling. We expect that with further\ndevelopment, EO transducers in thin-film lithium niobate can achieve near-unity\nefficiency with low optical pump power.\n