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arXiv · 1602.07833

A fault-tolerant addressable spin qubit in a natural silicon quantum dot

K. Takeda·J. Kamioka·T. Otsuka·J. Yoneda·T. Nakajima·M. R. Delbecq·S. Amaha·G. Allison·T. Kodera·S. Oda·S. Tarucha
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Abstract

Fault-tolerant quantum operation is a key requirement for the development of quantum computing. This has been realized in various solid-state systems including isotopically purified silicon which provides a nuclear spin free environment for the qubits, but not in industry standard natural (unpurified) silicon. Here we demonstrate an addressable fault-tolerant qubit using a natural silicon double quantum dot with a micromagnet optimally designed for fast spin control. This optimized design allows us to achieve the optimum Rabi oscillation quality factor Q = 140 at a Rabi frequency of 10 MHz in the frequency range two orders of magnitude higher than that achieved in previous studies. This leads to a qubit fidelity of 99.6 %, 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 from the industrial and quantum computing communities.

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K. Takeda, J. Kamioka, T. Otsuka, J. Yoneda, T. Nakajima, M. R. Delbecq, S. Amaha, G. Allison, T. Kodera, S. Oda, S. Tarucha. 2016-02-25. A fault-tolerant addressable spin qubit in a natural silicon quantum dot. https://doi.org/10.1126/sciadv.1600694

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