Simulating quantum systems on quantum computers*

In this presentation, we discuss a new mapping method—called symmetry configuration mapping (SCM)—that uses the symmetry of the physical system to isolate different parts of the computational space. As well as providing robustness against state leakage, this new approach allows the computation to be separated into a set of smaller independent calculations involving fewer quantum logic gate operations and fewer qubits. For a fluorine molecule, the numbers of quantum logic gate operations and qubits are reduced by factors of 3 and 4, respectively. These reductions have allowed us to solve for the full many-body ground state on the IBM Q “Poughkeepsie” quantum computer. As long as quantum computing resources remain limited, similar target-customized mappings are expected to be employed in quantum computing across all areas of application.