Learning Noise via Dynamical Decoupling of Entangled Qubits
- URL: http://arxiv.org/abs/2201.11173v1
- Date: Wed, 26 Jan 2022 20:22:38 GMT
- Title: Learning Noise via Dynamical Decoupling of Entangled Qubits
- Authors: Trevor McCourt, Charles Neill, Kenny Lee, Chris Quintana, Yu Chen,
Julian Kelly, V. N. Smelyanskiy, M. I. Dykman, Alexander Korotkov, Isaac L.
Chuang, A. G. Petukhov
- Abstract summary: Noise in entangled quantum systems is difficult to characterize due to many-body effects involving multiple degrees of freedom.
We develop and apply multi-qubit dynamical decoupling sequences that characterize noise that occurs during two-qubit gates.
- Score: 49.38020717064383
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Noise in entangled quantum systems is difficult to characterize due to
many-body effects involving multiple degrees of freedom. This noise poses a
challenge to quantum computing, where two-qubit gate performance is critical.
Here, we develop and apply multi-qubit dynamical decoupling sequences that
characterize noise that occurs during two-qubit gates. In our superconducting
system comprised of Transmon qubits with tunable couplers, we observe noise
that is consistent with flux fluctuations in the coupler that simultaneously
affects both qubits and induces noise in their entangling parameter. The effect
of this noise on the qubits is very different from the well-studied
single-qubit dephasing. Additionally, steps are observed in the decoupled
signals, implying the presence of non-Gaussian noise.
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