Measurement of correlated charge noise of two coupled silicon quantum dot qubits

Gate-defined quantum dots in silicon have shown to be a promising platform for encoding qubits due to their long coherence times and scalability with current industrial fabrication technology [1]. For these systems, charge noise due to fluctuating electric fields remains an important driver for their decoherence [2]; however, the correlation of this noise between qubits has not been extensively studied. In this talk, we discuss our results regarding this noise affecting two adjacent double quantum dots (DQDs) in a linear array Si/SiGe heterostructure device. We find the charge noise of the two DQDs becomes correlated with sufficiently strong coupling between the DQD pairs and the noise for each DQD is minimized when the detuning of the partner DQD reaches zero. We investigate how this correlation evolves as we tune the inter-dot coupling, and the mechanism behind this behavior is discussed.

[1] F. A. Zwanenburg, A. S. Dzurak, A. Morello, M. Y. Simmons, L. C. L. Hollenberg, G. Klimeck, S. Rogge, S. N. Coppersmith, and M. A. Eriksson, Silicon Quantum Electronics, (2012).

[2] G. Burkard, T. D. Ladd, J. M. Nichol, A. Pan, and J. R. Petta, Semiconductor Spin Qubits, (2021).