Engineering analog quantum chemistry Hamiltonians using cold atoms in optical lattices

TL;DR

This paper advances the use of ultra-cold fermionic atoms in optical lattices to simulate quantum chemistry Hamiltonians, improving experimental feasibility and understanding error sources for more accurate analog quantum simulations.

Contribution

It extends previous work by benchmarking conditions, analyzing errors, and simulating two-electron systems, enhancing the practicality of analog quantum chemistry simulations.

Findings

Less demanding experimental setups identified

Errors due to discretization and finite size effects analyzed and mitigated

Simulations of He and HeH+ molecules performed beyond initial examples

Abstract

Using quantum systems to efficiently solve quantum chemistry problems is one of the long-sought applications of near-future quantum technologies. In a recent work, ultra-cold fermionic atoms have been proposed for these purposes by showing us how to simulate in an analog way the quantum chemistry Hamiltonian projected in a lattice basis set. Here, we continue exploring this path and go beyond these first results in several ways. First, we numerically benchmark the working conditions of the analog simulator, and find less demanding experimental setups where chemistry-like behaviour in three-dimensions can still be observed. We also provide a deeper understanding of the errors of the simulation appearing due to discretization and finite size effects and provide a way to mitigate them. Finally, we benchmark the simulator characterizing the behaviour of two-electron atoms (He) and molecules (HeH$^+$) beyond the example considered in the original work.