Overlap-ADAPT-VQE: practical quantum chemistry on quantum computers via overlap-guided compact Ansätze

Abstract ADAPT-VQE is a robust algorithm for hybrid quantum-classical simulations of quantum chemical systems on near-term computers. While its iterative process systematically reaches the ground state energy, practical implementations are sensitive to local energy minima, leading over-parameterized ansätze. We introduce Overlap-ADAPT-VQE grow wave-functions by maximizing their overlap with any intermediate target wave-function that already captures some electronic correlation. By avoiding building ansatz in landscape strewn produces ultra-compact ansätze suitable high-accuracy initialization new ADAPT procedure. Significant advantages over observed strongly correlated including substantial savings circuit depth. Since this compression strategy can also be initialized accurate Selected-Configuration Interaction (SCI) classical wave-functions, it paves way chemically larger systems, and strengthens promise decisively surpassing chemistry through power computing.