Unitary-coupled restricted Boltzmann machine ansatz for quantum simulations

Abstract Neural-network quantum state (NQS) has attracted significant interests as a powerful wave-function ansatz to model phenomena. In particular, variant of NQS based on the restricted Boltzmann machine (RBM) been adapted ground spin lattices and electronic structures small molecules in devices. Despite these progresses, challenges remain with RBM-NQS-based simulations. this work, we present state-preparation protocol generate specific set complex-valued RBM-NQS, which name unitary-coupled circuits. Our proposal expands applicability prior works deal exclusively real-valued RBM-NQS for algorithms. With scheme, achieve (1) modeling wave functions, (2) using few one ancilla qubit simulate M hidden spins an RBM architecture, (3) avoiding post-selections improve scalability.