Driven qubit implementations in silicon-MOS devices
Abstract
This project sets out a detailed work plan for driven qubit implementations using spins confined in silicon metal-oxidesemiconductor (SiMOS) nanoscale devices. Driven qubits offer superior performance due to better protection against dephasing noise and provide the ultimate prospect of quantum computing at scale with a single, global control microwave field. This investigation builds on the pioneering technologies developed by Prof. Andrew Dzurak at UNSW using lithographically defined SiMOS quantum dots. These include the first single-shot electron spin readout in Si; first qubit in a P-atom; high-fidelity (FC = 99.6%) SiMOS quantum dot qubit in 28Si; and the first silicon two-qubit logic gate [Nature 467, 687 (2010); Nature 489, 541 (2012); Nature Nano 9, 981 (2014); Nature 526, 410 (2015)]. More recently, we demonstrated single qubit gates with exceedingly high fidelity [Nature Electronics 2, 151 (2019)]; operation of two-qubit gates at F_2Q=98% [Nature 569, 532 (2019)]; single-shot gate-based readout [Nature Nano 14, 437 (2019)]; qubits at low magnetic field with Pauli blockade readout [Nature Comms 10, 5500 (2019)]; coupling between an electron spin qubit and a 29Si nuclear spin qubit [Nature Nano 15, 13 (2020)]; operation of qubits above 1K temperatures [Nature 580, 350 (2020)]; multielectron single spin qubit [Nature Comms 11, 797 (2020)], and two-qubit processor [Nature Comms 12, 3228 (2021)]; and coherent spin shuttling [Nature Comms 12, 4114 (2021)]. The experimental program is based on the well-established SiMOS QD qubit platform developed at UNSW, and systematically builds towards an architecture for SiMOS-based quantum computing with driven spins. For this purpose, we aim to operate a 4-qubit device by Year-4, that can be used as a testbed for qubit benchmarking and qubit-qubit crosstalk in driven mode. Individual research streams include: (i) Driven qubit operation of 1-, 2, and 4-qubit devices with emphasis on the development of low noise, high quality factor dielectric cavities, characterizing sources of noise, improving gate fidelities, and benchmarking cross-correlated noise in multi-qubit devices; (ii) Shuttling of driven qubits for the purpose of evaluating the potential of a modular architecture with shuttled qubits in a global field; (iii) Operation of qubits at elevated temperatures (1.5 K) to assess the thermal impact of global control fields and implement closed-loop feedback to improve operational fidelities; (iv) Integration of parametric amplifiers into SiMOS device measurement systems to achieve improved qubit readout fidelities in all research streams, including under elevated temperatures due to the always-on global microwave field. This program builds on existing strong links between UNSW, USyd and HRL and incorporates new PIs to strengthen the collaboration, including: Developing RF readout resonators and integrating parametric amplifiers with our devices (Pla Ð UNSW); New theory support on gate optimization and closed-loop feedback (Hush Ð Q-CTRL); Continued theory support in architectures and multi-qubit QCVV (Bartlett Ð USyd); and Advanced device modelling support for SiMOS multi-dot devices (Kiselev, Ladd, Gyure Ð HRL/UCLA).
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Apr 26, 2023
- Source ID
- W911NF2310092
Entities
People
- Andrew S. Dzurak
Organizations
- Army Contracting Command
- National Security Agency
- University of New South Wales