SIMULTANEOUS MEASUREMENT OF COMMUTING OPERATORS

A computer-implemented method for determining a measurement value for each operator of a plurality of operators. The method comprises grouping the plurality of operators into one or more sets of mutually commuting operators, each set comprising one or more of the plurality of operators. Determining, for each set of operators: a subset of transformed operators based on the set of operators, such that the set of operators are equal to products of the subset of transformed operators; a mapping circuit based on the subset of transformed operators, wherein the mapping circuit comprises an arrangement of quantum gates configured to operate on a plurality of qubits in a quantum computer. Performing a measurement routine for each set of operators, the measurement routine comprising: preparing, using the plurality of qubits in the quantum computer, a trial state using a first arrangement of quantum gates; operating the mapping circuit on the plurality of qubits in the trial state; performing a measurement on each qubit of the plurality of qubits, to obtain a qubit measurement value for each qubit.