title: Three-Dimensional Proton Beam Writing of Optically Active Coherent Vacancy Spins in Silicon Carbide.
abstract: Constructing quantum devices comprises various challenging tasks, especially when concerning their nanoscale geometry. For quantum color centers, the traditional approach is to fabricate the device structure after the nondeterministic placement of the centers. Reversing this approach, we present the controlled generation of quantum centers in silicon carbide (SiC) by focused proton beam in a noncomplex manner without need for pre- or postirradiation treatment. The generation depth and resolution can be predicted by matching the proton energy to the material's stopping power, and the amount of quantum centers at one specific sample volume is tunable from ensembles of millions to discernible single photon emitters. We identify the generated centers as silicon vacancies through their characteristic magnetic resonance signatures and demonstrate that they possess a long spin-echo coherence time of 42 ± 20 μs at room temperature. Our approach hence enables the fabrication of quantum hybrid nanodevices based on SiC platform, where spin centers are integrated into p-i-n diodes, photonic cavities, and mechanical resonators.
authors.affiliation: Experimental Physics VI, Julius Maximilian University of Würzburg , 97074 Würzburg, Germany.|National Institutes for Quantum and Radiological Science and Technology (QST) , Takasaki, Gunma 370-1292, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Kraus
authors.affiliation: Experimental Physics VI, Julius Maximilian University of Würzburg , 97074 Würzburg, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Simin
authors.affiliation: Experimental Physics VI, Julius Maximilian University of Würzburg , 97074 Würzburg, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Kasper
authors.affiliation: Faculty of Science and Technology, Gunma University , Kiryu, Gunma 376-8515, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Suda
authors.affiliation: Faculty of Science and Technology, Gunma University , Kiryu, Gunma 376-8515, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Kawabata
authors.affiliation: Faculty of Science and Technology, Gunma University , Kiryu, Gunma 376-8515, Japan.
authors.forename: W
authors.initials: W
authors.lastname: Kada
authors.affiliation: National Institutes for Quantum and Radiological Science and Technology (QST) , Takasaki, Gunma 370-1292, Japan.|Graduate School of Science and Engineering, Saitama University , Saitama 338-8570, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Honda
authors.affiliation: Graduate School of Science and Engineering, Saitama University , Saitama 338-8570, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Hijikata
authors.affiliation: National Institutes for Quantum and Radiological Science and Technology (QST) , Takasaki, Gunma 370-1292, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Ohshima
authors.affiliation: Experimental Physics VI, Julius Maximilian University of Würzburg , 97074 Würzburg, Germany.|Bavarian Center for Applied Energy Research (ZAE Bayern) , 97074 Würzburg, Germany.
authors.forename: V
authors.identifier: 0000-0001-8725-9573
authors.initials: V
authors.lastname: Dyakonov
authors.affiliation: Experimental Physics VI, Julius Maximilian University of Würzburg , 97074 Würzburg, Germany.
authors.forename: G V
authors.identifier: 0000-0003-1807-3534
authors.initials: GV
authors.lastname: Astakhov
keywords: Silicon carbide; atom-scale defects; proton beam writing; quantum coherence