1
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Sangregorio E, Calcagno L, Medina E, Crnjac A, Jakšic M, Vignati A, Romano F, Milluzzo G, De Napoli M, Camarda M. Single-Ion Counting with an Ultra-Thin-Membrane Silicon Carbide Sensor. MATERIALS (BASEL, SWITZERLAND) 2023; 16:7692. [PMID: 38138833 PMCID: PMC10744360 DOI: 10.3390/ma16247692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 12/12/2023] [Accepted: 12/14/2023] [Indexed: 12/24/2023]
Abstract
In recent times, ion implantation has received increasing interest for novel applications related to deterministic material doping on the nanoscale, primarily for the fabrication of solid-state quantum devices. For such applications, precise information concerning the number of implanted ions and their final position within the implanted sample is crucial. In this work, we present an innovative method for the detection of single ions of MeV energy by using a sub-micrometer ultra-thin silicon carbide sensor operated as an in-beam counter of transmitted ions. The SiC sensor signals, when compared to a Passivated Implanted Planar Silicon detector signal, exhibited a 96.5% ion-detection confidence, demonstrating that the membrane sensors can be utilized for high-fidelity ion counting. Furthermore, we assessed the angular straggling of transmitted ions due to the interaction with the SiC sensor, employing the scanning knife-edge method of a focused ion microbeam. The lateral dimension of the ion beam with and without the membrane sensor was compared to the SRIM calculations. The results were used to discuss the potential of such experimental geometry in deterministic ion-implantation schemes as well as other applications.
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Affiliation(s)
- Enrico Sangregorio
- Department of Physics and Astronomy “Ettore Majorana”, University of Catania (Italy), Via Santa Sofia 64, 95123 Catania, Italy;
- STLab srl, Via Anapo 53, 95126 Catania, Italy; (E.M.); (M.C.)
| | - Lucia Calcagno
- Department of Physics and Astronomy “Ettore Majorana”, University of Catania (Italy), Via Santa Sofia 64, 95123 Catania, Italy;
| | - Elisabetta Medina
- STLab srl, Via Anapo 53, 95126 Catania, Italy; (E.M.); (M.C.)
- Physics Department, Università degli Studi di Torino, Via Pietro Giuria 1, 10125 Turin, Italy;
- INFN—National Institute for Nuclear Physics, Turin Division, Via Pietro Giuria 1, 10125 Turin, Italy
| | - Andreo Crnjac
- Division of Experimental Physics, Ruđer Bošković Institute, 10000 Zagreb, Croatia;
| | - Milko Jakšic
- Division of Experimental Physics, Ruđer Bošković Institute, 10000 Zagreb, Croatia;
| | - Anna Vignati
- Physics Department, Università degli Studi di Torino, Via Pietro Giuria 1, 10125 Turin, Italy;
- INFN—National Institute for Nuclear Physics, Turin Division, Via Pietro Giuria 1, 10125 Turin, Italy
| | - Francesco Romano
- INFN—National Institute for Nuclear Physics, Catania Division, Via S. Sofia 64, 95123 Catania, Italy; (F.R.); (G.M.); (M.D.N.)
| | - Giuliana Milluzzo
- INFN—National Institute for Nuclear Physics, Catania Division, Via S. Sofia 64, 95123 Catania, Italy; (F.R.); (G.M.); (M.D.N.)
| | - Marzio De Napoli
- INFN—National Institute for Nuclear Physics, Catania Division, Via S. Sofia 64, 95123 Catania, Italy; (F.R.); (G.M.); (M.D.N.)
| | - Massimo Camarda
- STLab srl, Via Anapo 53, 95126 Catania, Italy; (E.M.); (M.C.)
- SenSiC GmbH, DeliveryLAB, 5234 Villigen, Switzerland
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2
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Yang Y, Liu M, Yang Z, Lin WS, Chen L, Tan J. Enhanced Antibacterial Effect on Zirconia Implant Abutment by Silver Linear-Beam Ion Implantation. J Funct Biomater 2023; 14:jfb14010046. [PMID: 36662093 PMCID: PMC9865340 DOI: 10.3390/jfb14010046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Revised: 12/30/2022] [Accepted: 01/11/2023] [Indexed: 01/15/2023] Open
Abstract
Peri-implant lesions, such as peri-implant mucositis and peri-implantitis, are bacterial-derived diseases that happen around dental implants, compromising the long-term stability and esthetics of implant restoration. Here, we report a surface-modification method on zirconia implant abutment using silver linear-beam ion implantation to reduce the bacterial growth around the implant site, thereby decreasing the prevalence of peri-implant lesions. The surface characteristics of zirconia after ion implantation was evaluated using energy dispersive spectroscopy, X-ray photoelectron spectroscopy, and a contact-angle device. The antibacterial properties of implanted zirconia were evaluated using Streptococcus mutans and Porphyromonas gingivalis. The biocompatibility of the material surface was evaluated using human gingival fibroblasts. Our study shows that the zirconia surface was successfully modified with silver nanoparticles by using the ion-implantation method. The surface modification remained stable, and the silver-ion elution was below 1 ppm after one-month of storage. The modified surface can effectively eliminate bacterial growth, while the normal gingiva's cell growth is not interfered with. The results of the study demonstrate that a silver-ion-implanted zirconia surface possesses good antibacterial properties and good biocompatibility. The surface modification using silver-ion implantation is a promising method for future usage.
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Affiliation(s)
- Yang Yang
- Department of Prosthodontics, Peking University School, Hospital of Stomatology, Beijing 100081, China
- National Center of Stomatology, National Clinical Research Center for Oral Diseases, National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing Key Laboratory of Digital Stomatology, Research Center of Engineering and Technology for Computerized Dentistry Ministry of Health, NMPA Key Laboratory for Dental Materials, No. 22, Zhongguancun South Avenue, Haidian District, Beijing 100081, China
| | - Mingyue Liu
- National Center of Stomatology, National Clinical Research Center for Oral Diseases, National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing Key Laboratory of Digital Stomatology, Research Center of Engineering and Technology for Computerized Dentistry Ministry of Health, NMPA Key Laboratory for Dental Materials, No. 22, Zhongguancun South Avenue, Haidian District, Beijing 100081, China
- First Clinical Division, Peking University School, Hospital of Stomatology, Beijing 100081, China
| | - Zhen Yang
- Department of Prosthodontics, Peking University School, Hospital of Stomatology, Beijing 100081, China
- National Center of Stomatology, National Clinical Research Center for Oral Diseases, National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing Key Laboratory of Digital Stomatology, Research Center of Engineering and Technology for Computerized Dentistry Ministry of Health, NMPA Key Laboratory for Dental Materials, No. 22, Zhongguancun South Avenue, Haidian District, Beijing 100081, China
| | - Wei-Shao Lin
- Department of Prosthodontics, Indiana University School of Dentistry, Indianapolis, IN 46202, USA
| | - Li Chen
- Department of Prosthodontics, Peking University School, Hospital of Stomatology, Beijing 100081, China
- National Center of Stomatology, National Clinical Research Center for Oral Diseases, National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing Key Laboratory of Digital Stomatology, Research Center of Engineering and Technology for Computerized Dentistry Ministry of Health, NMPA Key Laboratory for Dental Materials, No. 22, Zhongguancun South Avenue, Haidian District, Beijing 100081, China
- Correspondence:
| | - Jianguo Tan
- Department of Prosthodontics, Peking University School, Hospital of Stomatology, Beijing 100081, China
- National Center of Stomatology, National Clinical Research Center for Oral Diseases, National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing Key Laboratory of Digital Stomatology, Research Center of Engineering and Technology for Computerized Dentistry Ministry of Health, NMPA Key Laboratory for Dental Materials, No. 22, Zhongguancun South Avenue, Haidian District, Beijing 100081, China
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3
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Jakob AM, Robson SG, Schmitt V, Mourik V, Posselt M, Spemann D, Johnson BC, Firgau HR, Mayes E, McCallum JC, Morello A, Jamieson DN. Deterministic Shallow Dopant Implantation in Silicon with Detection Confidence Upper-Bound to 99.85% by Ion-Solid Interactions. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2103235. [PMID: 34632636 DOI: 10.1002/adma.202103235] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 08/17/2021] [Indexed: 06/13/2023]
Abstract
Silicon chips containing arrays of single dopant atoms can be the material of choice for classical and quantum devices that exploit single donor spins. For example, group-V donors implanted in isotopically purified 28 Si crystals are attractive for large-scale quantum computers. Useful attributes include long nuclear and electron spin lifetimes of 31 P, hyperfine clock transitions in 209 Bi or electrically controllable 123 Sb nuclear spins. Promising architectures require the ability to fabricate arrays of individual near-surface dopant atoms with high yield. Here, an on-chip detector electrode system with 70 eV root-mean-square noise (≈20 electrons) is employed to demonstrate near-room-temperature implantation of single 14 keV 31 P+ ions. The physics model for the ion-solid interaction shows an unprecedented upper-bound single-ion-detection confidence of 99.85 ± 0.02% for near-surface implants. As a result, the practical controlled silicon doping yield is limited by materials engineering factors including surface gate oxides in which detected ions may stop. For a device with 6 nm gate oxide and 14 keV 31 P+ implants, a yield limit of 98.1% is demonstrated. Thinner gate oxides allow this limit to converge to the upper-bound. Deterministic single-ion implantation can therefore be a viable materials engineering strategy for scalable dopant architectures in silicon devices.
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Affiliation(s)
- Alexander M Jakob
- School of Physics, ARC Centre for Quantum Computation and Communication Technology, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Simon G Robson
- School of Physics, ARC Centre for Quantum Computation and Communication Technology, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Vivien Schmitt
- School of Electrical Engineering and Telecommunications, ARC Centre for Quantum Computation and Communication Technology, UNSW Sydney, Sydney, NSW, 2052, Australia
| | - Vincent Mourik
- School of Electrical Engineering and Telecommunications, ARC Centre for Quantum Computation and Communication Technology, UNSW Sydney, Sydney, NSW, 2052, Australia
| | - Matthias Posselt
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden, 01328, Saxony, Germany
| | - Daniel Spemann
- School of Physics, ARC Centre for Quantum Computation and Communication Technology, University of Melbourne, Parkville, VIC, 3010, Australia
- Leibniz Institute of Surface Engineering (IOM), Leipzig, 04318, Saxony, Germany
| | - Brett C Johnson
- School of Physics, ARC Centre for Quantum Computation and Communication Technology, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Hannes R Firgau
- School of Electrical Engineering and Telecommunications, ARC Centre for Quantum Computation and Communication Technology, UNSW Sydney, Sydney, NSW, 2052, Australia
| | - Edwin Mayes
- RMIT Microscopy and Microanalysis Facility, RMIT University, Melbourne, VIC, 3001, Australia
| | - Jeffrey C McCallum
- School of Physics, ARC Centre for Quantum Computation and Communication Technology, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Andrea Morello
- School of Electrical Engineering and Telecommunications, ARC Centre for Quantum Computation and Communication Technology, UNSW Sydney, Sydney, NSW, 2052, Australia
| | - David N Jamieson
- School of Physics, ARC Centre for Quantum Computation and Communication Technology, University of Melbourne, Parkville, VIC, 3010, Australia
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4
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Ma Dzik MT, Laucht A, Hudson FE, Jakob AM, Johnson BC, Jamieson DN, Itoh KM, Dzurak AS, Morello A. Conditional quantum operation of two exchange-coupled single-donor spin qubits in a MOS-compatible silicon device. Nat Commun 2021; 12:181. [PMID: 33420013 PMCID: PMC7794236 DOI: 10.1038/s41467-020-20424-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 12/02/2020] [Indexed: 11/09/2022] Open
Abstract
Silicon nanoelectronic devices can host single-qubit quantum logic operations with fidelity better than 99.9%. For the spins of an electron bound to a single-donor atom, introduced in the silicon by ion implantation, the quantum information can be stored for nearly 1 second. However, manufacturing a scalable quantum processor with this method is considered challenging, because of the exponential sensitivity of the exchange interaction that mediates the coupling between the qubits. Here we demonstrate the conditional, coherent control of an electron spin qubit in an exchange-coupled pair of 31P donors implanted in silicon. The coupling strength, J = 32.06 ± 0.06 MHz, is measured spectroscopically with high precision. Since the coupling is weaker than the electron-nuclear hyperfine coupling A ≈ 90 MHz which detunes the two electrons, a native two-qubit controlled-rotation gate can be obtained via a simple electron spin resonance pulse. This scheme is insensitive to the precise value of J, which makes it suitable for the scale-up of donor-based quantum computers in silicon that exploit the metal-oxide-semiconductor fabrication protocols commonly used in the classical electronics industry.
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Affiliation(s)
- Mateusz T Ma Dzik
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, UNSW Sydney, Sydney, NSW, 2052, Australia
| | - Arne Laucht
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, UNSW Sydney, Sydney, NSW, 2052, Australia
| | - Fay E Hudson
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, UNSW Sydney, Sydney, NSW, 2052, Australia
| | - Alexander M Jakob
- Centre for Quantum Computation and Communication Technology, School of Physics, University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Brett C Johnson
- Centre for Quantum Computation and Communication Technology, School of Physics, University of Melbourne, Melbourne, VIC, 3010, Australia
| | - David N Jamieson
- Centre for Quantum Computation and Communication Technology, School of Physics, University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Kohei M Itoh
- School of Fundamental Science and Technology, Keio University, 3-14-1, Hiyoshi, 223-8522, Japan
| | - Andrew S Dzurak
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, UNSW Sydney, Sydney, NSW, 2052, Australia
| | - Andrea Morello
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, UNSW Sydney, Sydney, NSW, 2052, Australia.
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5
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Fröch JE, Bahm A, Kianinia M, Mu Z, Bhatia V, Kim S, Cairney JM, Gao W, Bradac C, Aharonovich I, Toth M. Versatile direct-writing of dopants in a solid state host through recoil implantation. Nat Commun 2020; 11:5039. [PMID: 33028814 PMCID: PMC7541527 DOI: 10.1038/s41467-020-18749-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 09/07/2020] [Indexed: 01/29/2023] Open
Abstract
Modifying material properties at the nanoscale is crucially important for devices in nano-electronics, nanophotonics and quantum information. Optically active defects in wide band gap materials, for instance, are critical constituents for the realisation of quantum technologies. Here, we demonstrate the use of recoil implantation, a method exploiting momentum transfer from accelerated ions, for versatile and mask-free material doping. As a proof of concept, we direct-write arrays of optically active defects into diamond via momentum transfer from a Xe+ focused ion beam (FIB) to thin films of the group IV dopants pre-deposited onto a diamond surface. We further demonstrate the flexibility of the technique, by implanting rare earth ions into the core of a single mode fibre. We conclusively show that the presented technique yields ultra-shallow dopant profiles localised to the top few nanometres of the target surface, and use it to achieve sub-50 nm positional accuracy. The method is applicable to non-planar substrates with complex geometries, and it is suitable for applications such as electronic and magnetic doping of atomically-thin materials and engineering of near-surface states of semiconductor devices.
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Affiliation(s)
- Johannes E Fröch
- School of Mathematical and Physical Sciences, University of Technology Sydney, Ultimo, NSW, 2007, Australia
| | - Alan Bahm
- Thermo Fisher Scientific, Hillsboro, OR, 97124, USA
| | - Mehran Kianinia
- School of Mathematical and Physical Sciences, University of Technology Sydney, Ultimo, NSW, 2007, Australia
| | - Zhao Mu
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore
| | - Vijay Bhatia
- Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Sejeong Kim
- School of Mathematical and Physical Sciences, University of Technology Sydney, Ultimo, NSW, 2007, Australia
| | - Julie M Cairney
- Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Weibo Gao
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore
| | - Carlo Bradac
- School of Mathematical and Physical Sciences, University of Technology Sydney, Ultimo, NSW, 2007, Australia.,Department of Physics & Astronomy, Trent University, 1600 West Bank Dr., Peterborough, ON, K9J 0G2, Canada
| | - Igor Aharonovich
- School of Mathematical and Physical Sciences, University of Technology Sydney, Ultimo, NSW, 2007, Australia. .,ARC Centre of Excellence for Transformative Meta-Optical Systems (TMOS), University of Technology Sydney, Ultimo, NSW, 2007, Australia.
| | - Milos Toth
- School of Mathematical and Physical Sciences, University of Technology Sydney, Ultimo, NSW, 2007, Australia. .,ARC Centre of Excellence for Transformative Meta-Optical Systems (TMOS), University of Technology Sydney, Ultimo, NSW, 2007, Australia.
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6
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Yıldırım O, Hilliard D, Arekapudi SSPK, Fowley C, Cansever H, Koch L, Ramasubramanian L, Zhou S, Böttger R, Lindner J, Faßbender J, Hellwig O, Deac AM. Ion-Irradiation-Induced Cobalt/Cobalt Oxide Heterostructures: Printing 3D Interfaces. ACS APPLIED MATERIALS & INTERFACES 2020; 12:9858-9864. [PMID: 32009381 DOI: 10.1021/acsami.9b13503] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Interfaces separating ferromagnetic (FM) layers from non-ferromagnetic layers offer unique properties due to spin-orbit coupling and symmetry breaking, yielding effects such as exchange bias, perpendicular magnetic anisotropy, spin-pumping, spin-transfer torques, and conversion between charge and spin currents and vice versa. These interfacial phenomena play crucial roles in magnetic data storage and transfer applications, which require the formation of FM nanostructures embedded in non-ferromagnetic matrices. Here, we investigate the possibility of creating such nanostructures by ion irradiation. We study the effect of lateral confinement on the ion-irradiation-induced reduction of nonmagnetic metal oxides (e.g., antiferro- or paramagnetic) to form ferromagnetic metals. Our findings are later exploited to form three-dimensional magnetic interfaces between Co, CoO, and Pt by spatial-selective irradiation of CoO/Pt multilayers. We demonstrate that the mechanical displacement of O atoms plays a crucial role in the reduction from insulating, non-ferromagnetic cobalt oxides to metallic cobalt. Metallic cobalt yields both perpendicular magnetic anisotropy in the generated Co/Pt nanostructures and, at low temperatures, exchange bias at vertical interfaces between Co and CoO. If pushed to the limit of ion-irradiation technology, this approach could, in principle, enable the creation of densely packed, atomic-scale ferromagnetic point-contact spin-torque oscillator (STO) networks or conductive channels for current-confined-path-based current perpendicular-to-plane giant magnetoresistance read heads.
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Affiliation(s)
- Oğuz Yıldırım
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research , Bautzner Landstr. 400 , 01328 Dresden , Germany
- Empa-Swiss Federal Laboratories for Materials Science and Technology , Ueberlandstr. 129 , 8600 Dübendorf , Switzerland
| | - Donovan Hilliard
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research , Bautzner Landstr. 400 , 01328 Dresden , Germany
- Chemnitz University of Technology, Institute of Physics , Reichenhainer Str. 70 , 09126 Chemnitz , Germany
| | | | - Ciarán Fowley
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research , Bautzner Landstr. 400 , 01328 Dresden , Germany
| | - Hamza Cansever
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research , Bautzner Landstr. 400 , 01328 Dresden , Germany
- Institute of Physics of Solids , Dresden University of Technology , 01062 Dresden , Germany
| | - Leopold Koch
- Chemnitz University of Technology, Institute of Physics , Reichenhainer Str. 70 , 09126 Chemnitz , Germany
| | - Lakshmi Ramasubramanian
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research , Bautzner Landstr. 400 , 01328 Dresden , Germany
| | - Shengqiang Zhou
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research , Bautzner Landstr. 400 , 01328 Dresden , Germany
| | - Roman Böttger
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research , Bautzner Landstr. 400 , 01328 Dresden , Germany
| | - Jürgen Lindner
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research , Bautzner Landstr. 400 , 01328 Dresden , Germany
| | - Jürgen Faßbender
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research , Bautzner Landstr. 400 , 01328 Dresden , Germany
- Institute of Physics of Solids , Dresden University of Technology , 01062 Dresden , Germany
| | - Olav Hellwig
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research , Bautzner Landstr. 400 , 01328 Dresden , Germany
- Chemnitz University of Technology, Institute of Physics , Reichenhainer Str. 70 , 09126 Chemnitz , Germany
| | - Alina M Deac
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research , Bautzner Landstr. 400 , 01328 Dresden , Germany
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7
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Hensen B, Wei Huang W, Yang CH, Wai Chan K, Yoneda J, Tanttu T, Hudson FE, Laucht A, Itoh KM, Ladd TD, Morello A, Dzurak AS. A silicon quantum-dot-coupled nuclear spin qubit. NATURE NANOTECHNOLOGY 2020; 15:13-17. [PMID: 31819245 DOI: 10.1038/s41565-019-0587-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 11/05/2019] [Indexed: 06/10/2023]
Abstract
Single nuclear spins in the solid state are a potential future platform for quantum computing1-3, because they possess long coherence times4-6 and offer excellent controllability7. Measurements can be performed via localized electrons, such as those in single atom dopants8,9 or crystal defects10-12. However, establishing long-range interactions between multiple dopants or defects is challenging13,14. Conversely, in lithographically defined quantum dots, tunable interdot electron tunnelling allows direct coupling of electron spin-based qubits in neighbouring dots15-20. Moreover, the compatibility with semiconductor fabrication techniques21 may allow for scaling to large numbers of qubits in the future. Unfortunately, hyperfine interactions are typically too weak to address single nuclei. Here we show that for electrons in silicon metal-oxide-semiconductor quantum dots the hyperfine interaction is sufficient to initialize, read out and control single 29Si nuclear spins. This approach combines the long coherence times of nuclear spins with the flexibility and scalability of quantum dot systems. We demonstrate high-fidelity projective readout and control of the nuclear spin qubit, as well as entanglement between the nuclear and electron spins. Crucially, we find that both the nuclear spin and electron spin retain their coherence while moving the electron between quantum dots. Hence we envision long-range nuclear-nuclear entanglement via electron shuttling3. Our results establish nuclear spins in quantum dots as a powerful new resource for quantum processing.
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Affiliation(s)
- Bas Hensen
- Center for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, The University of New South Wales, Sydney, New South Wales, Australia
- Delft University of Technology, Delft, The Netherlands
| | - Wister Wei Huang
- Center for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, The University of New South Wales, Sydney, New South Wales, Australia
| | - Chih-Hwan Yang
- Center for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, The University of New South Wales, Sydney, New South Wales, Australia
| | - Kok Wai Chan
- Center for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, The University of New South Wales, Sydney, New South Wales, Australia
| | - Jun Yoneda
- Center for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, The University of New South Wales, Sydney, New South Wales, Australia
| | - Tuomo Tanttu
- Center for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, The University of New South Wales, Sydney, New South Wales, Australia
| | - Fay E Hudson
- Center for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, The University of New South Wales, Sydney, New South Wales, Australia
| | - Arne Laucht
- Center for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, The University of New South Wales, Sydney, New South Wales, Australia
| | - Kohei M Itoh
- School of Fundamental Science and Technology, Keio University, Yokohama, Japan
| | | | - Andrea Morello
- Center for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, The University of New South Wales, Sydney, New South Wales, Australia
| | - Andrew S Dzurak
- Center for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, The University of New South Wales, Sydney, New South Wales, Australia.
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8
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Groot-Berning K, Kornher T, Jacob G, Stopp F, Dawkins ST, Kolesov R, Wrachtrup J, Singer K, Schmidt-Kaler F. Deterministic Single-Ion Implantation of Rare-Earth Ions for Nanometer-Resolution Color-Center Generation. PHYSICAL REVIEW LETTERS 2019; 123:106802. [PMID: 31573288 DOI: 10.1103/physrevlett.123.106802] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Indexed: 05/24/2023]
Abstract
Single dopant atoms or dopant-related defect centers in a solid state matrix are of particular importance among the physical systems proposed for quantum computing and communication, due to their potential to realize a scalable architecture compatible with electronic and photonic integrated circuits. Here, using a deterministic source of single laser-cooled Pr^{+} ions, we present the fabrication of arrays of praseodymium color centers in yttrium-aluminum-garnet substrates. The beam of single Pr^{+} ions is extracted from a Paul trap and focused down to 30(9) nm. Using a confocal microscope, we determine a conversion yield into active color centers of up to 50% and realize a placement precision of 34 nm.
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Affiliation(s)
- Karin Groot-Berning
- QUANTUM, Institut für Physik, Universität Mainz, Staudingerweg 7, 55128 Mainz, Germany
| | - Thomas Kornher
- Physikalisches Institut, Universität Stuttgart, 70569 Stuttgart, Germany
| | - Georg Jacob
- QUANTUM, Institut für Physik, Universität Mainz, Staudingerweg 7, 55128 Mainz, Germany
| | - Felix Stopp
- QUANTUM, Institut für Physik, Universität Mainz, Staudingerweg 7, 55128 Mainz, Germany
| | - Samuel T Dawkins
- Experimentalphysik I, Institut für Physik, Universität Kassel, Heinrich-Plett-Straße 40, 34132 Kassel, Germany
| | - Roman Kolesov
- Physikalisches Institut, Universität Stuttgart, 70569 Stuttgart, Germany
| | - Jörg Wrachtrup
- Physikalisches Institut, Universität Stuttgart, 70569 Stuttgart, Germany
| | - Kilian Singer
- Experimentalphysik I, Institut für Physik, Universität Kassel, Heinrich-Plett-Straße 40, 34132 Kassel, Germany
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9
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GeV n complexes for silicon-based room-temperature single-atom nanoelectronics. Sci Rep 2018; 8:18054. [PMID: 30575772 PMCID: PMC6303345 DOI: 10.1038/s41598-018-36441-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 11/15/2018] [Indexed: 11/15/2022] Open
Abstract
We propose germanium-vacancy complexes (GeVn) as a viable ingredient to exploit single-atom quantum effects in silicon devices at room temperature. Our predictions, motivated by the high controllability of the location of the defect via accurate single-atom implantation techniques, are based on ab-initio Density Functional Theory calculations within a parameterfree screened-dependent hybrid functional scheme, suitable to provide reliable bandstructure energies and defect-state wavefunctions. The resulting defect-related excited states, at variance with those arising from conventional dopants such as phosphorous, turn out to be deep enough to ensure device operation up to room temperature and exhibit a far more localized wavefunction.
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10
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Räcke P, Spemann D, Gerlach JW, Rauschenbach B, Meijer J. Detection of small bunches of ions using image charges. Sci Rep 2018; 8:9781. [PMID: 29955102 PMCID: PMC6023920 DOI: 10.1038/s41598-018-28167-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 06/12/2018] [Indexed: 11/26/2022] Open
Abstract
A concept for detection of charged particles in a single fly-by, e.g. within an ion optical system for deterministic implantation, is presented. It is based on recording the image charge signal of ions moving through a detector, comprising a set of cylindrical electrodes. This work describes theoretical and practical aspects of image charge detection (ICD) and detector design and its application in the context of real time ion detection. It is shown how false positive detections are excluded reliably, although the signal-to-noise ratio is far too low for time-domain analysis. This is achieved by applying a signal threshold detection scheme in the frequency domain, which - complemented by the development of specialised low-noise preamplifier electronics - will be the key to developing single ion image charge detection for deterministic implantation.
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Affiliation(s)
- Paul Räcke
- Universität Leipzig, Felix Bloch Institute for Solid State Physics, Linnéstr. 5, 04103, Leipzig, Germany.
- Leibniz Joint Lab "Single Ion Implantation", Permoserstr. 15, 04318, Leipzig, Germany.
| | - Daniel Spemann
- Leibniz Joint Lab "Single Ion Implantation", Permoserstr. 15, 04318, Leipzig, Germany
- Leibniz Institute of Surface Engineering (IOM), Permoserstr. 15, 04318, Leipzig, Germany
| | - Jürgen W Gerlach
- Leibniz Joint Lab "Single Ion Implantation", Permoserstr. 15, 04318, Leipzig, Germany
- Leibniz Institute of Surface Engineering (IOM), Permoserstr. 15, 04318, Leipzig, Germany
| | - Bernd Rauschenbach
- Universität Leipzig, Felix Bloch Institute for Solid State Physics, Linnéstr. 5, 04103, Leipzig, Germany
- Leibniz Joint Lab "Single Ion Implantation", Permoserstr. 15, 04318, Leipzig, Germany
- Leibniz Institute of Surface Engineering (IOM), Permoserstr. 15, 04318, Leipzig, Germany
| | - Jan Meijer
- Universität Leipzig, Felix Bloch Institute for Solid State Physics, Linnéstr. 5, 04103, Leipzig, Germany
- Leibniz Joint Lab "Single Ion Implantation", Permoserstr. 15, 04318, Leipzig, Germany
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11
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Pacheco JL, Singh M, Perry DL, Wendt JR, Ten Eyck G, Manginell RP, Pluym T, Luhman DR, Lilly MP, Carroll MS, Bielejec E. Ion implantation for deterministic single atom devices. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2017; 88:123301. [PMID: 29289172 DOI: 10.1063/1.5001520] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We demonstrate a capability of deterministic doping at the single atom level using a combination of direct write focused ion beam and solid-state ion detectors. The focused ion beam system can position a single ion to within 35 nm of a targeted location and the detection system is sensitive to single low energy heavy ions. This platform can be used to deterministically fabricate single atom devices in materials where the nanostructure and ion detectors can be integrated, including donor-based qubits in Si and color centers in diamond.
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Affiliation(s)
- J L Pacheco
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - M Singh
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - D L Perry
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - J R Wendt
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - G Ten Eyck
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - R P Manginell
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - T Pluym
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - D R Luhman
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - M P Lilly
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - M S Carroll
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - E Bielejec
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
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Pastuović Ž, Siegele R, Capan I, Brodar T, Sato SI, Ohshima T. Deep level defects in 4H-SiC introduced by ion implantation: the role of single ion regime. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2017; 29:475701. [PMID: 28972198 DOI: 10.1088/1361-648x/aa908c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We characterized intrinsic deep level defects created in ion collision cascades which were produced by patterned implantation of single accelerated 2.0 MeV He and 600 keV H ions into n-type 4H-SiC epitaxial layers using a fast-scanning reduced-rate ion microbeam. The initial deep level transient spectroscopy measurement performed on as-grown material in the temperature range 150-700 K revealed the presence of only two electron traps, Z 1/2 (0.64 eV) and EH6/7 (1.84 eV) assigned to the two different charge state transitions of the isolated carbon vacancy, V C (=/0) and (0/+). C-V measurements of as-implanted samples revealed the increasing free carrier removal with larger ion fluence values, in particular at depth corresponding to a vicinity of the end of an ion range. The first DLTS measurement of as-implanted samples revealed formation of additional deep level defects labelled as ET1 (0.35 eV), ET2 (0.65 eV) and EH3 (1.06 eV) which were clearly distinguished from the presence of isolated carbon vacancies (Z 1/2 and EH6/7 defects) in increased concentrations after implantations either by He or H ions. Repeated C-V measurements showed that a partial net free-carrier recovery occurred in as-implanted samples upon the low-temperature annealing following the first DLTS measurement. The second DLTS measurement revealed the almost complete removal of ET2 defect and the partial removal of EH3 defect, while the concentrations of Z 1/2 and EH6/7 defects increased, due to the low temperature annealing up to 700 K accomplished during the first temperature scan. We concluded that the ET2 and EH3 defects: (i) act as majority carrier removal traps, (ii) exhibit a low thermal stability and (iii) can be related to the simple point-like defects introduced by light ion implantation, namely interstitials and/or complex of interstitials and vacancies in both carbon and silicon sub-lattices.
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Affiliation(s)
- Željko Pastuović
- Centre for Accelerator Science, Australian Nuclear Science and Technology Organisation, 1 New Illawarra Rd, Lucas Heights NSW 2234, Australia
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Tosi G, Mohiyaddin FA, Schmitt V, Tenberg S, Rahman R, Klimeck G, Morello A. Silicon quantum processor with robust long-distance qubit couplings. Nat Commun 2017; 8:450. [PMID: 28878207 PMCID: PMC5587611 DOI: 10.1038/s41467-017-00378-x] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Accepted: 06/20/2017] [Indexed: 11/11/2022] Open
Abstract
Practical quantum computers require a large network of highly coherent qubits, interconnected in a design robust against errors. Donor spins in silicon provide state-of-the-art coherence and quantum gate fidelities, in a platform adapted from industrial semiconductor processing. Here we present a scalable design for a silicon quantum processor that does not require precise donor placement and leaves ample space for the routing of interconnects and readout devices. We introduce the flip-flop qubit, a combination of the electron-nuclear spin states of a phosphorus donor that can be controlled by microwave electric fields. Two-qubit gates exploit a second-order electric dipole-dipole interaction, allowing selective coupling beyond the nearest-neighbor, at separations of hundreds of nanometers, while microwave resonators can extend the entanglement to macroscopic distances. We predict gate fidelities within fault-tolerance thresholds using realistic noise models. This design provides a realizable blueprint for scalable spin-based quantum computers in silicon.Quantum computers will require a large network of coherent qubits, connected in a noise-resilient way. Tosi et al. present a design for a quantum processor based on electron-nuclear spins in silicon, with electrical control and coupling schemes that simplify qubit fabrication and operation.
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Affiliation(s)
- Guilherme Tosi
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering & Telecommunications, UNSW, Sydney, NSW, 2052, Australia.
| | - Fahd A Mohiyaddin
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering & Telecommunications, UNSW, Sydney, NSW, 2052, Australia
- Quantum Computing Institute, Oak Ridge National Laboratory, Oak Ridge, 37830, TN, USA
| | - Vivien Schmitt
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering & Telecommunications, UNSW, Sydney, NSW, 2052, Australia
| | - Stefanie Tenberg
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering & Telecommunications, UNSW, Sydney, NSW, 2052, Australia
| | - Rajib Rahman
- Network for Computational Nanotechnology, Purdue University, West Lafayette, IN, 47907, USA
| | - Gerhard Klimeck
- Network for Computational Nanotechnology, Purdue University, West Lafayette, IN, 47907, USA
| | - Andrea Morello
- Centre for Quantum Computation and Communication Technology, School of Electrical Engineering & Telecommunications, UNSW, Sydney, NSW, 2052, Australia.
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Martin TL, London AJ, Jenkins B, Hopkin SE, Douglas JO, Styman PD, Bagot PAJ, Moody MP. Comparing the Consistency of Atom Probe Tomography Measurements of Small-Scale Segregation and Clustering Between the LEAP 3000 and LEAP 5000 Instruments. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2017; 23:227-237. [PMID: 28441978 DOI: 10.1017/s1431927617000356] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The local electrode atom probe (LEAP) has become the primary instrument used for atom probe tomography measurements. Recent advances in detector and laser design, together with updated hit detection algorithms, have been incorporated into the latest LEAP 5000 instrument, but the implications of these changes on measurements, particularly the size and chemistry of small clusters and elemental segregations, have not been explored. In this study, we compare data sets from a variety of materials with small-scale chemical heterogeneity using both a LEAP 3000 instrument with 37% detector efficiency and a 532-nm green laser and a new LEAP 5000 instrument with a manufacturer estimated increase to 52% detector efficiency, and a 355-nm ultraviolet laser. In general, it was found that the number of atoms within small clusters or surface segregation increased in the LEAP 5000, as would be expected by the reported increase in detector efficiency from the LEAP 3000 architecture, but subtle differences in chemistry were observed which are attributed to changes in the way multiple hit detection is calculated using the LEAP 5000.
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Affiliation(s)
- Tomas L Martin
- 1Department of Materials,University of Oxford,Parks Road,Oxford,OX1 3PH,UK
| | - Andrew J London
- 1Department of Materials,University of Oxford,Parks Road,Oxford,OX1 3PH,UK
| | - Benjamin Jenkins
- 1Department of Materials,University of Oxford,Parks Road,Oxford,OX1 3PH,UK
| | - Sarah E Hopkin
- 1Department of Materials,University of Oxford,Parks Road,Oxford,OX1 3PH,UK
| | - James O Douglas
- 1Department of Materials,University of Oxford,Parks Road,Oxford,OX1 3PH,UK
| | - Paul D Styman
- 2National Nuclear Laboratory,Building D5,Culham Science Centre,Abingdon,Oxfordshire,OX14 3DB,UK
| | - Paul A J Bagot
- 1Department of Materials,University of Oxford,Parks Road,Oxford,OX1 3PH,UK
| | - Michael P Moody
- 1Department of Materials,University of Oxford,Parks Road,Oxford,OX1 3PH,UK
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15
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Humble TS, Ericson MN, Jakowski J, Huang J, Britton C, Curtis FG, Dumitrescu EF, Mohiyaddin FA, Sumpter BG. A computational workflow for designing silicon donor qubits. NANOTECHNOLOGY 2016; 27:424002. [PMID: 27641513 DOI: 10.1088/0957-4484/27/42/424002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Developing devices that can reliably and accurately demonstrate the principles of superposition and entanglement is an on-going challenge for the quantum computing community. Modeling and simulation offer attractive means of testing early device designs and establishing expectations for operational performance. However, the complex integrated material systems required by quantum device designs are not captured by any single existing computational modeling method. We examine the development and analysis of a multi-staged computational workflow that can be used to design and characterize silicon donor qubit systems with modeling and simulation. Our approach integrates quantum chemistry calculations with electrostatic field solvers to perform detailed simulations of a phosphorus dopant in silicon. We show how atomistic details can be synthesized into an operational model for the logical gates that define quantum computation in this particular technology. The resulting computational workflow realizes a design tool for silicon donor qubits that can help verify and validate current and near-term experimental devices.
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Affiliation(s)
- Travis S Humble
- Quantum Computing Institute, Oak Ridge National Laboratory, Oak Ridge, TN, USA. Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA. Bredesen Center for Interdisciplinary Research, University of Tennessee, Knoxville, TN, USA
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16
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Jehl X, Niquet YM, Sanquer M. Single donor electronics and quantum functionalities with advanced CMOS technology. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2016; 28:103001. [PMID: 26871255 DOI: 10.1088/0953-8984/28/10/103001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Recent progresses in quantum dots technology allow fundamental studies of single donors in various semiconductor nanostructures. For the prospect of applications figures of merits such as scalability, tunability, and operation at relatively large temperature are of prime importance. Beyond the case of actual dopant atoms in a host crystal, similar arguments hold for small enough quantum dots which behave as artificial atoms, for instance for single spin control and manipulation. In this context, this experimental review focuses on the silicon-on-insulator devices produced within microelectronics facilities with only very minor modifications to the current industrial CMOS process and tools. This is required for scalability and enabled by shallow trench or mesa isolation. It also paves the way for real integration with conventional circuits, as illustrated by a nanoscale device coupled to a CMOS circuit producing a radio-frequency drive on-chip. At the device level we emphasize the central role of electrostatics in etched silicon nanowire transistors, which allows to understand the characteristics in the full range from zero to room temperature.
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Affiliation(s)
- Xavier Jehl
- Université Grenoble Alpes, INAC, F-38000 Grenoble, France. CEA, INAC-SPSMS F-38000 Grenoble, France
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17
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Schofield SR, Rogge S. Single dopants in semiconductors. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2015; 27:150301. [PMID: 25782475 DOI: 10.1088/0953-8984/27/15/150301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Affiliation(s)
- Steven R Schofield
- London Centre for Nanotechnology, and Department of Physics and Astronomy, University College London, London, WC1H 0AH, UK. Centre for Quantum Computation and Communication Technology, School of Physics, The University of New South Wales, Sydney, NSW 2052, Australia
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