Quantifying the effect of gate errors on variational quantum eigensolvers for quantum chemistry

Understand

Variational quantum eigensolvers (VQEs) are leading candidates to demonstrate near-term quantum advantage.

• Here, we conduct density-matrix simulations of leading gate-based VQEs for a range of molecules.
• We numerically quantify their level of tolerable depolarizing gate-errors.
• We find that: (i) The best-performing VQEs require gate-error probabilities between $10^{-6}$ and $10^{-4}$ ( $10^{-4}$ and $10^{-2}$ with error mitigation) to predict, within chemical accuracy, ground-state energies of small molecules with $4-14$ orbitals.