Development of Ultrahigh-precision Ion Implantation System Based on Laser-cooled Ion Source

Hosaka Koichi, Seiji Hosoya, Kashiwagi Hirotsugu, Miyawaki Nobumasa, Ishii Yasuyuki, Yamagata Ryohei, Narumi Kazumasa, Yuri Yosuke, Onoda Shinobu, Kento Muroo, K. Ito, Okamoto Hiromi

Published Jul 29, 2025• 0 citations

OpenAlex

Abstract

Nitrogen-vacancy (NV) centers in diamond are gaining attention as room-temperature quantum bits, with potential applications in quantum sensing, quantum information processing, and quantum communication. Precise positioning of NV centers is crucial for creating efficient single-photon sources using optical resonators and quantum memories for quantum interface, etc. Generally, broad ion beam implantation through nanohole fabricated by electron beam lithography has been widely used for precise creation of NV centers. There are several reports of deterministic NV creation by using pulsed fs- or ps-laser irradiations. In addition, focusing ion beam implantation provides a route towards scalable quantum information processing [3-6]. In this study, we are developing an inherently deterministic single-ion implantation method based on a linear Paul trap (LPT) as a single-ion source, since the laser-cooling technique can be applied to the trap system to obtain ultralow-emittance ions and manipulate single ions one by one. The QST system uses doubly charged ions cooled with calcium ions, allowing 100 keV ion implantation in diamond.

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