TY - JOUR
T1 - A fault-tolerant addressable spin qubit in a natural silicon quantum dot
AU - Takeda, Kenta
AU - Kamioka, Jun
AU - Otsuka, Tomohiro
AU - Yoneda, Jun
AU - Nakajima, Takashi
AU - Delbecq, Matthieu R.
AU - Amaha, Shinichi
AU - Allison, Giles
AU - Kodera, Tetsuo
AU - Oda, Shunri
AU - Tarucha, Seigo
N1 - Funding Information:
We thank R. Sugawara and T. Obata for technical contributions. This work was supported financially by the ImPACT Program of Council for Science, Technology and Innovation (Cabinet Office, Government of Japan); CREST (Japan Science and Technology Agency); Toyota Physical and Chemical Research Institute Scholars; the RIKEN Incentive Research Project; a Yazaki Memorial Foundation for Science and Technology research grant; a Japan Prize Foundation research grant; an Advanced Technology Institute research grant; a Murata Science Foundation research grant; Kakenhi Grants-in-Aid (nos. 26220710, 26709023, 26630151, 25800173, and 16H00817); a Strategic Information and Communications R&D Promotion Programme; an Izumi Science and Technology Foundation research grant; and a TEPCO Memorial Foundation research grant.
PY - 2016/8
Y1 - 2016/8
N2 - Fault-tolerant quantum computing requires high-fidelity qubits. This has been achieved in various solid-state systems, including isotopically purified silicon, but is yet to be accomplished in industry-standard natural (unpurified) silicon, mainly as a result of the dephasing caused by residual nuclear spins. This high fidelity can be achieved by speeding up the qubit operation and/or prolonging the dephasing time, that is, increasing the Rabi oscillation quality factor Q (the Rabi oscillation decay time divided by the p rotation time). In isotopically purified silicon quantum dots, only the second approach has been used, leaving the qubit operation slow. We apply the first approach to demonstrate an addressable fault-tolerant qubit using a natural silicon double quantum dot with a micromagnet that is optimally designed for fast spin control. This optimized design allows access to Rabi frequencies up to 35 MHz, which is two orders of magnitude greater than that achieved in previous studies. We find the optimum Q = 140 in such high-frequency range at a Rabi frequency of 10 MHz. This leads to a qubit fidelity of 99.6% measured via randomized benchmarking, which is the highest reported for natural silicon qubits and comparable to that obtained in isotopically purified silicon quantum dot–based qubits. This result can inspire contributions to quantum computing from industrial communities.
AB - Fault-tolerant quantum computing requires high-fidelity qubits. This has been achieved in various solid-state systems, including isotopically purified silicon, but is yet to be accomplished in industry-standard natural (unpurified) silicon, mainly as a result of the dephasing caused by residual nuclear spins. This high fidelity can be achieved by speeding up the qubit operation and/or prolonging the dephasing time, that is, increasing the Rabi oscillation quality factor Q (the Rabi oscillation decay time divided by the p rotation time). In isotopically purified silicon quantum dots, only the second approach has been used, leaving the qubit operation slow. We apply the first approach to demonstrate an addressable fault-tolerant qubit using a natural silicon double quantum dot with a micromagnet that is optimally designed for fast spin control. This optimized design allows access to Rabi frequencies up to 35 MHz, which is two orders of magnitude greater than that achieved in previous studies. We find the optimum Q = 140 in such high-frequency range at a Rabi frequency of 10 MHz. This leads to a qubit fidelity of 99.6% measured via randomized benchmarking, which is the highest reported for natural silicon qubits and comparable to that obtained in isotopically purified silicon quantum dot–based qubits. This result can inspire contributions to quantum computing from industrial communities.
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U2 - 10.1126/sciadv.1600694
DO - 10.1126/sciadv.1600694
M3 - Article
C2 - 27536725
AN - SCOPUS:84995616406
VL - 2
JO - Science advances
JF - Science advances
SN - 2375-2548
IS - 8
M1 - e1600694
ER -