Quantum Simulation of Strongly Correlated Molecules with Rydberg Atom Arrays

Of the potential applications for near-term programmable quantum simulators, one of the most promising isstudying quantum chemistry and materials problems. In this work, we develop a simulation framework, combining classical computational chemistry techniques with quantum simulation, for studying low-energy properties of certain molecules and materials with strong spin correlations. For such systems, classical electronic structure algorithms can efficiently compute effective spin Hamiltonians that capture the low-energy physics. However, eigenstates of these models are often strongly correlated and require methods which can capture large quantum fluctuations. As such, we propose to use Rydberg atom arrays to encode and simulate such effective Hamiltonians and develop a hardware efficient Hamiltonian simulation based on dynamical reconfiguration and multi-qubit Rydberg gates. The framework also includes algorithms for the extraction of detailed spectral information from time dynamics, including observables relevant for chemistry, through snapshot measurements and ancilla-assisted control. As a proof of concept, we ultimately apply the developed methodology to simulate and analyze organometallic catalysts, single-molecular magnets, and propose near-term simulations of 2D magnetic materials.