Hybrid Quantum-Classical Computer System and Method for Performing Function Inversion

A hybrid quantum-classical computing system for use with:

• a Boolean function which maps at least one input bit to at least one output bit;
• a seed output value satisfying at least one condition;
• and
• a set of constraints such that a satisfying assignment of the constraints corresponds to a specific input value being mapped by the Boolean function to the seed output value;
• the hybrid quantum-classical computing system comprising:
• a quantum computing component having a plurality of qubits and a qubit controller that manipulates the plurality of qubits;
• and
• a classical computing component storing machine-readable instructions that, when executed by the classical computer, control the classical computer to cooperate with the quantum computer to:
• translate the constraints into interactions between quantum spins;
• form, from the interactions, an Ising Hamiltonian whose ground state encodes a set of states of the specific input value that are consistent with the set of constraints;
• perform, on the quantum computing component, a quantum optimization algorithm to generate an approximation to the ground state of the Ising Hamiltonian;
• and
• measure the approximation to the ground state of the Ising Hamiltonian, on the quantum computing component, to obtain a plurality of input bits which are a satisfying assignment of the set of constraints.