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arXiv · 2203.07331

Effective non-local parity-dependent couplings in qubit chains

Maximilian Nägele·Christian Schweizer·Federico Roy·Stefan Filipp
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Abstract

For the efficient implementation of quantum algorithms, practical ways to generate many-body entanglement are a basic requirement. Specifically, coupling multiple qubit pairs at once can be advantageous and can lead to multi-qubit operations useful in the construction of hardware-tailored algorithms. Here we harness the simultaneous coupling of qubits on a chain and engineer a set of non-local parity-dependent quantum operations suitable for a wide range of applications. The resulting effective long-range couplings directly implement a parametrizable Trotter-step for Jordan-Wigner fermions and can be used for simulations of quantum dynamics, efficient state generation in variational quantum eigensolvers, parity measurements for error-correction schemes, and the generation of efficient multi-qubit gates. Moreover, we present numerical simulations of the gate operation in a superconducting quantum circuit architecture, which show a high gate fidelity of $>99.9\%$ for realistic experimental parameters.

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Maximilian Nägele, Christian Schweizer, Federico Roy, Stefan Filipp. 2022-03-14. Effective non-local parity-dependent couplings in qubit chains. https://doi.org/10.1103/physrevresearch.4.033166

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