A Hardware-Aware Heuristic for the Qubit Mapping Problem in the NISQ Era

TL;DR

This paper introduces a hardware-aware heuristic algorithm for qubit mapping in NISQ quantum computers, improving circuit fidelity and reducing additional gates by considering hardware calibration data during compilation.

Contribution

The proposed HA algorithm is the first to incorporate hardware calibration data into qubit mapping, enhancing fidelity and efficiency over existing methods.

Findings

Outperforms state-of-the-art in circuit fidelity

Reduces the number of additional gates needed

Effective on IBM quantum hardware

Abstract

Due to several physical limitations in the realisation of quantum hardware, today's quantum computers are qualified as Noisy Intermediate-Scale Quantum (NISQ) hardware. NISQ hardware is characterized by a small number of qubits (50 to a few hundred) and noisy operations. Moreover, current realisations of superconducting quantum chips do not have the ideal all-to-all connectivity between qubits but rather at most a nearest-neighbour connectivity. All these hardware restrictions add supplementary low-level requirements. They need to be addressed before submitting the quantum circuit to an actual chip. Satisfying these requirements is a tedious task for the programmer. Instead, the task of adapting the quantum circuit to a given hardware is left to the compiler. In this paper, we propose a Hardware-Aware mapping transition algorithm (HA) that takes the calibration data into account with the aim to improve the overall fidelity of the circuit. Evaluation results on IBM quantum hardware show that our HA approach can outperform the state of the art both in terms of the number of additional gates and circuit fidelity.