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arXiv · 2109.04179

Optimal Mapping for Near-Term Quantum Architectures based on Rydberg Atoms

Abstract

Quantum algorithms promise quadratic or exponential speedups for applications in cryptography, chemistry and material sciences. The topologies of today's quantum computers offer limited connectivity, leading to significant overheads for implementing such quantum algorithms. One-dimensional topology displacements that remedy these limits have been recently demonstrated for architectures based on Rydberg atoms, and they are possible in principle in photonic and ion trap architectures. We present the first optimal quantum circuit-to-architecture mapping algorithm that exploits such one-dimensional topology displacements. We benchmark our method on quantum circuits with up to 15 qubits and investigate the improvements compared with conventional mapping based on inserting swap gates into the quantum circuits. Depending on underlying technology parameters, our approach can decrease the quantum circuit depth by up to 58% and increase the fidelity by up to 29%. We also study runtime and fidelity requirements on one-dimensional displacements and swap gates to derive conditions under which one-dimensional topology displacements provide benefits.

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BibTeXRIS

Sebastian Brandhofer, Hans Peter Büchler, Ilia Polian. 2021-09-09. Optimal Mapping for Near-Term Quantum Architectures based on Rydberg Atoms. https://arxiv.org/abs/2109.04179

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