Abstract: A system and method for initializing and optimizing a variational quantum circuit on a hybrid quantum-classical computer, comprising a set of gates and a set of initial parameters representing a model of a physical system. A quantum circuit is generated comprising a set of smaller contiguous subcomponents which can be independently optimized to minimize a property of the physical system, such as ground state energy or the absorption spectrum of a molecule. At least one entangling gate is introduced between at least two circuit subcomponents. The initial parameters of the circuit components may be set according to values obtained from a parameter library. Once the initial parameters are set, the circuit components of the quantum computer proceed to optimization, which is independent for each subcomponent of the system. The optimization method may also include the use of a variational quantum eigensolver (VQE).

Abstract: A computer-implemented method produces a representation of a pure quantum state from a classical model. The classical model has a plurality of parameters. The method includes: (A) selecting a set of outcomes from a library of outcomes of a quantum circuit, wherein the library of outcomes comprises a plurality of measurement pairs sampled from the quantum circuit, each measurement pair comprising a quantum measurement and a corresponding measurement basis; and (B) updating values of the plurality of parameters of the classical model to minimize a value of a distance measure between the classical model and the set of outcomes, thereby producing the updated classical model, wherein the updated classical model has the updated values of the plurality of parameters.

Abstract: A quantum computer or a hybrid quantum-classical (HQC) computer leverages the power of noisy intermediate-scale quantum (NISQ) superconducting quantum processors at and/or beyond the supremacy regime to evaluate the ground state energy of an electronic structure Hamiltonian.

Abstract: A quantum computer or a hybrid quantum-classical (HQC) computer leverages the power of noisy intermediate-scale quantum (NISQ) superconducting quantum processors at and/or beyond the supremacy regime to evaluate the ground state energy of an electronic structure Hamiltonian.