Simulations of scattering processes are essential in understanding the physics of our universe. Computing relevant scattering quantities from ab initio methods is extremely difficult on classical devices because of the substantial computational resources needed. This work reports the development of an algorithm that makes it possible to obtain phase shifts for generic non-relativistic elastic scattering processes on a quantum computer. Such algorithm is based on extracting phase shifts from the direct implementation of the real-time evolution. The algorithm is improved by a variational procedure, making it more accurate and resistant to the noise of quantum . The reliability of the algorithm is first demonstrated by means of classical numerical simulations for different potentials, and later tested on existing quantum hardware, specifically on IBM quantum processors.
This work was supported in part by the U.S. De- partment of Energy, Office of Science, Office of Nuclear Physics, InQubator for Quantum Simulation (IQuS) (https://iqus.uw.edu) under Award Number DOE (NP) Award DE-SC0020970 via the program on Quan- tum Horizons: QIS Research and Innovation for Nuclear Science. This work was prepared in part by LLNL under Contract No. DE- AC52-07NA27344 with sup- port from the U.S. Department of Energy, Office of Sci- ence, Office of Nuclear Physics (under Work Proposal No. SCW1730). This work was enabled by the use of advanced compu- tational, storage, and networking infrastructure provided by the Hyak supercomputer system at the University of Washington (https://hyak.uw.edu/).
