Document Type
Article
Publication Date
7-2025
Publisher
American Chemical Society
Source Publication
Jouranal of Physical Chemistry A
Source ISSN
1089-5639
Abstract
We explore how the fundamental problems in quantum molecular dynamics can be modeled using classical simulators (emulators) of quantum computers and the actual quantum hardware available to us today. The list of problems we tackle includes propagation of a free wave packet, vibration of a harmonic oscillator, and tunneling through a barrier. Each of these problems starts with the initial wave packet setup. Although Qiskit provides a general method for initializing wave functions, in most cases it generates deep quantum circuits. While these circuits perform well on noiseless simulators, they suffer from excessive noise on quantum hardware. To overcome this issue, we designed a shallower quantum circuit for preparing a Gaussian-like initial wave packet, which improves the performance of real hardware. Next, quantum circuits are implemented to apply the kinetic and potential energy operators for the evolution of a wave function over time. The results of our modeling on classical emulators of quantum hardware agree perfectly with the results obtained using the traditional (classical) methods. This serves as a benchmark and demonstrates that the quantum algorithms and Qiskit codes we developed are accurate. However, the results obtained on the actual quantum hardware available today, such as IBM’s superconducting qubits and IonQ’s trapped ions, indicate large discrepancies due to hardware limitations. This work highlights both the potential and challenges of using quantum computers to solve fundamental quantum molecular dynamics problems.
Recommended Citation
Kuanysheva, Tamila; Kendrick, Brian K.; Cincio, Lukasz; and Babikov, Dmitri, "Quantum Simulation of Molecular Dynamics Processes─A Benchmark Study Using a Classical Simulator and Present-Day Quantum Hardware" (2025). Chemistry Faculty Research and Publications. 1105.
https://epublications.marquette.edu/chem_fac/1105
Comments
Accepted version. Journal of Physical Chemistry A, Vol. 129, No. 28 (July 2025): 6470-6481. DOI. © 2025 American Chemical Society. Used with permission.