Patent ID: 11334693

Abstract:
Computer systems and methods for constructing a model of the noise afflicting a quantum computer comprising a plurality of qubits are provided. A graph G that describes a conditional independence structure of the noise is obtained. The graph G includes a node for each qubit in the plurality of qubits. The noise afflicting the quantum computer is logically reduced to Pauli noise. The graph G is broken into a plurality of sets. Each respective set Cj in the plurality of sets (i) corresponds a respective qubit j in the plurality of qubits and (ii) comprises a representation of the respective qubit j and the parent qubits ∂+j in the graph G. For each respective set Cj in the plurality of sets, a corresponding local conditional probability distribution Pr(ej|e∂+j) is characterized in which ejϵj is a Pauli error on the jth qubit. The characterization is performed by a procedure that comprises estimating a local Pauli fidelity for the respective set Cj, thereby learning the model of the noise afflicting the quantum computer.