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arXiv · 2205.06555

Quantum control of tunable-coupling transmons using dynamical invariants of motion

Hilario Espinós·Iván Panadero·Juan José García-Ripoll·Erik Torrontegui
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Abstract

We analyse the implementation of a fast nonadiabatic CZ gate between two transmon qubits with tuneable coupling. The gate control method is based on a theory of dynamical invariants which leads to reduced leakage and robustness against decoherence. The gate is based on a description of the resonance between the $|11\rangle$ and $|20\rangle$ using an effective Hamiltonian with the 6 lowest energy states. A modification of the invariants method allows us to take into account the higher-order perturbative corrections of this effective model. This enables a gate fidelity several orders of magnitude higher than other quasiadiabatic protocols, with gate times that approach the theoretical limit.

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Hilario Espinós, Iván Panadero, Juan José García-Ripoll, Erik Torrontegui. 2022-05-13. Quantum control of tunable-coupling transmons using dynamical invariants of motion. https://arxiv.org/abs/2205.06555

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