Quantum emulation of the transient dynamics in the multistate Landau-Zener model

Stehli, A., Brehm, J. D., Wolz, T., Schneider, A., Rotzinger, H., Weides, M. and Ustinov, A. V. (2023) Quantum emulation of the transient dynamics in the multistate Landau-Zener model. npj Quantum Information, 9(1), 61. (doi: 10.1038/s41534-023-00731-7)

Abstract

Quantum simulation is one of the most promising near term applications of quantum computing. Especially, systems with a large Hilbert space are hard to solve for classical computers and thus ideal targets for a simulation with quantum hardware. In this work, we study experimentally the transient dynamics in the multistate Landau-Zener model as a function of the Landau-Zener velocity. The underlying Hamiltonian is emulated by superconducting quantum circuit, where a tunable transmon qubit is coupled to a bosonic mode ensemble comprising four lumped element microwave resonators. We investigate the model for different initial states: Due to our circuit design, we are not limited to merely exciting the qubit, but can also pump the harmonic modes via a dedicated drive line. Here, the nature of the transient dynamics depends on the average photon number in the excited resonator. The greater effective coupling strength between qubit and higher Fock states results in a quasi-adiabatic transition, where coherent quantum oscillations are suppressed without the introduction of additional loss channels. Our experiments pave the way for more complex simulations with qubits coupled to an engineered bosonic mode spectrum.

• Item Type: Articles
• Additional Information: Open Access funding enabled and organized by Projekt DEAL. This work was supported by the European Research Council (ERC) under the Grant Agreement No. 648011, Deutsche Forschungsgemeinschaft (DFG) projects INST 121384/138-1FUGG and WE 4359-7, EPSRC Hub in Quantum Computing and Simulation EP/T001062/1, and the Initiative and Networking Fund of the Helmholtz Association. A.S. acknowledges support from the Landesgraduiertenförderung Baden-Württemberg (LGF), J.D.B. acknowledges support from the Studienstiftung des Deutschen Volkes. T.W. acknowledges support from the Helmholtz International Research School for Teratronics (HIRST).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Weides, Professor Martin
• Authors: Stehli, A., Brehm, J. D., Wolz, T., Schneider, A., Rotzinger, H., Weides, M., and Ustinov, A. V.
• College/School: College of Science and Engineering > School of Engineering > Electronics and Nanoscale Engineering
• Journal Name: npj Quantum Information
• Publisher: Nature Research
• ISSN: 2056-6387
• ISSN (Online): 2056-6387
• Copyright Holders: Copyright © 2023 The Authors
• First Published: First published in npj Quantum Information 9(1):61
• Publisher Policy: Reproduced under a Creative Commons License

Project Code	Award No	Project Name	Principal Investigator	Funder's Name	Funder Ref	Lead Dept
306059		EPSRC Hub for Quantum Computing and Simulation	Martin Weides	Engineering and Physical Sciences Research Council (EPSRC)	EP/T001062/1	ENG - Electronics & Nanoscale Engineering