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Journal of Physics Conference Series

Focusing grating couplers for radio-frequency surface ion traps

Timur Abbasov, Ivan A. Kazakov, I. Sherstov, Sergey M. Kontorov, Arkadi Shipulin, Franko Küeppers, Kirill Lakhmanskiy

Published Nov 1, 2021• 1 citation
Publisher

Abstract

Abstract We present a photonic integrated circuit design with multiple focusing grating couplers that can be used in a surface ion trap. This system allows transferring laser radiation from different laser sources to the ion trapped 240 μm above the surface for further manipulations.
DOI
10.1088/1742-6596/2015/1/012001

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We report the development and experimental testing of focusing grating couplers (FGCs) designed for integration with surface ion traps, aiming to advance compact ion-based technologies for next-generation quantum sensors to be used in ion frequency standards, gravimetry, and quantum computing. Through analytical calculations, we optimized the simulation and fabrication processes. Using numerical simulations, we further optimized the focusing configuration of the grating couplers to achieve a focal point approximately 210 µm above the chip surface. The fabricated focusing couplers were experimentally tested and confirmed to effectively focus laser radiation at a height of 200-210 µm above the chip surface.
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