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arXiv · 2212.10395

Reqomp: Space-constrained Uncomputation for Quantum Circuits

Anouk Paradis·Benjamin Bichsel·Martin Vechev
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Abstract

Quantum circuits must run on quantum computers with tight limits on qubit and gate counts. To generate circuits respecting both limits, a promising opportunity is exploiting uncomputation to trade qubits for gates. We present Reqomp, a method to automatically synthesize correct and efficient uncomputation of ancillae while respecting hardware constraints. For a given circuit, Reqomp can offer a wide range of trade-offs between tightly constraining qubit count or gate count. Our evaluation demonstrates that Reqomp can significantly reduce the number of required ancilla qubits by up to 96%. On 80% of our benchmarks, the ancilla qubits required can be reduced by at least 25% while never incurring a gate count increase beyond 28%.

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Anouk Paradis, Benjamin Bichsel, Martin Vechev. 2022-12-20. Reqomp: Space-constrained Uncomputation for Quantum Circuits. https://doi.org/10.22331/q-2024-02-19-1258

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