Squash 2: A Hierarchical Scalable Quantum Mapper Considering Ancilla Sharing

TL;DR

This paper introduces Requp, a multi-core quantum processor architecture, and Squash 2, a scalable quantum mapper that efficiently maps large quantum algorithms by sharing ancilla qubits across cores.

Contribution

It proposes a hierarchical quantum mapping approach with shared ancilla qubits and a scalable mapper for large quantum circuits, enhancing quantum hardware utilization.

Findings

Squash 2 effectively handles large-scale quantum algorithms.

Shared ancilla qubits improve resource efficiency.

Requp architecture supports flexible quantum instruction execution.

Abstract

We present a multi-core reconfigurable quantum processor architecture, called Requp, which supports a hierarchical approach to mapping a quantum algorithm while sharing physical and logical ancilla qubits. Each core is capable of performing any quantum instruction. Moreover, we introduce a scalable quantum mapper, called Squash 2, which divides a given quantum circuit into a number of quantum modules---each module is divided into k parts such that each part will run on one of k available cores. Experimental results demonstrate that Squash~2 can handle large-scale quantum algorithms while providing an effective mechanism for sharing ancilla qubits.