TY - JOUR
T1 - Optimized electrical control of a Si/SiGe spin qubit in the presence of an induced frequency shift
AU - Takeda, K.
AU - Yoneda, J.
AU - Otsuka, T.
AU - Nakajima, T.
AU - Delbecq, M. R.
AU - Allison, G.
AU - Hoshi, Y.
AU - Usami, N.
AU - Itoh, K. M.
AU - Oda, S.
AU - Kodera, T.
AU - Tarucha, S.
N1 - Funding Information:
We thank the Microwave Research Group in Caltech for technical support. This work was supported financially by Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST) (JPMJCR15N2 and JPMJCR1675) and the ImPACT Program of Council for Science, Technology and Innovation (Cabinet Office, Government of Japan). K.T. acknowledges support from JSPS KAKENHI grant number JP17K14078. J.Y., T.O., and T.N. acknowledge support from RIKEN Incentive Research Projects. T.O. acknowledges support from Precursory Research for Embryonic Science and Technology (PRESTO) (JPMJPR16N3), JSPS KAKENHI grant numbers JP16H00817 and JP17H05187, Advanced Technology Institute Research Grant, the Murata Science Foundation Research Grant, Izumi Science and Technology Foundation Research Grant, TEPCO Memorial Foundation Research Grant, The Thermal and Electric Energy Technology Foundation Research Grant, The Telecommunications Advancement Foundation Research Grant, Futaba Electronics Memorial Foundation Research Grant and Foundation for Promotion of Material Science and Technology of Japan (MST) Foundation Research Grant. K.M.I. acknowledges support from JSPS KAKENHI grant number JP26220602 and JSPS Core-to-Core Program. T.K. acknowledges support from JSPS KAKENHI grant numbers JP26709023 and JP16F16806. S.T. acknowledges support from JSPS KAKENHI grant numbers JP26220710 and JP16H02204.
Publisher Copyright:
© The Author(s) 2018.
PY - 2018/12/1
Y1 - 2018/12/1
N2 - Electron spins confined in quantum dots are an attractive system to realize high-fidelity qubits owing to their long coherence time. With the prolonged spin coherence time, however, the control fidelity can be limited by systematic errors rather than decoherence, making characterization and suppression of their influence crucial for further improvement. Here we report that the control fidelity of Si/SiGe spin qubits can be limited by the microwave-induced frequency shift of electric dipole spin resonance and it can be improved by optimization of control pulses. As we increase the control microwave amplitude, we observe a shift of the qubit resonance frequency, in addition to the increasing Rabi frequency. We reveal that this limits control fidelity with a conventional amplitude-modulated microwave pulse below 99.8%. In order to achieve a gate fidelity >99.9%, we introduce a quadrature control method, and validate this approach experimentally by randomized benchmarking. Our finding facilitates realization of an ultra-high-fidelity qubit with electron spins in quantum dots.
AB - Electron spins confined in quantum dots are an attractive system to realize high-fidelity qubits owing to their long coherence time. With the prolonged spin coherence time, however, the control fidelity can be limited by systematic errors rather than decoherence, making characterization and suppression of their influence crucial for further improvement. Here we report that the control fidelity of Si/SiGe spin qubits can be limited by the microwave-induced frequency shift of electric dipole spin resonance and it can be improved by optimization of control pulses. As we increase the control microwave amplitude, we observe a shift of the qubit resonance frequency, in addition to the increasing Rabi frequency. We reveal that this limits control fidelity with a conventional amplitude-modulated microwave pulse below 99.8%. In order to achieve a gate fidelity >99.9%, we introduce a quadrature control method, and validate this approach experimentally by randomized benchmarking. Our finding facilitates realization of an ultra-high-fidelity qubit with electron spins in quantum dots.
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U2 - 10.1038/s41534-018-0105-z
DO - 10.1038/s41534-018-0105-z
M3 - Article
AN - SCOPUS:85062556290
SN - 2056-6387
VL - 4
JO - npj Quantum Information
JF - npj Quantum Information
IS - 1
M1 - 54
ER -