Massively parallel quantum computer simulator, eleven years later

TL;DR

This paper presents an improved massively parallel quantum computer simulator capable of simulating up to 48 qubits on supercomputers, demonstrating near-ideal scaling and benchmarking quantum algorithms on state-of-the-art hardware.

Contribution

It introduces adaptive wave function encoding to reduce memory use and extends the simulator to handle larger qubit systems on modern supercomputers.

Findings

Simulates up to 48 qubits on top supercomputers.

Achieves close-to-ideal weak-scaling behavior.

Successfully benchmarks quantum algorithms like Shor's on large qubit systems.

Abstract

A revised version of the massively parallel simulator of a universal quantum computer, described in this journal eleven years ago, is used to benchmark various gate-based quantum algorithms on some of the most powerful supercomputers that exist today. Adaptive encoding of the wave function reduces the memory requirement by a factor of eight, making it possible to simulate universal quantum computers with up to 48 qubits on the Sunway TaihuLight and on the K computer. The simulator exhibits close-to-ideal weak-scaling behavior on the Sunway TaihuLight,on the K computer, on an IBM Blue Gene/Q, and on Intel Xeon based clusters, implying that the combination of parallelization and hardware can track the exponential scaling due to the increasing number of qubits. Results of executing simple quantum circuits and Shor's factorization algorithm on quantum computers containing up to 48 qubits are presented.