Simulating quantum many-body dynamics on a current digital quantum computer

• Published in: npj quantum information Vol. 5; no. 1; pp. 1 - 13
• Main Authors: Smith, Adam, Kim, M. S., Pollmann, Frank, Knolle, Johannes
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 28-11-2019; Nature Publishing Group
• Subjects: 639/766/1130/1064; 639/766/119; 639/766/483/3926; Classical and Quantum Gravitation; Computers; Localization; Physics; Physics and Astronomy; Quantum Computing; Quantum Field Theories; Quantum Information Technology; Quantum Physics; Relativity Theory; Spintronics; String Theory
• ISSN: 2056-6387; 2056-6387
• DOI: 10.1038/s41534-019-0217-0

Universal quantum computers are potentially an ideal setting for simulating many-body quantum dynamics that is out of reach for classical digital computers. We use state-of-the-art IBM quantum computers to study paradigmatic examples of condensed matter physics—we simulate the effects of disorder and interactions on quantum particle transport, as well as correlation and entanglement spreading. Our benchmark results show that the quality of the current machines is below what is necessary for quantitatively accurate continuous-time dynamics of observables and reachable system sizes are small comparable to exact diagonalization. Despite this, we are successfully able to demonstrate clear qualitative behaviour associated with localization physics and many-body interaction effects.