Quantum readout error mitigation by stochastic matrix inversion

A computer readable medium on which is stored non-transitory computer-executable code, which when executed by a classical computer causes a quantum computer to:

• perform a plurality of quantum measurements on plurality of qubits having predetermined plurality of states to obtain a plurality of measurement outputs;
• select a model for a matrix linking the predetermined plurality of states to the plurality of measurement outputs, the model having a plurality of model parameters, wherein a number of the plurality of model parameters grows less than exponentially with a number of the plurality of states;
• train the plurality of model parameters to minimize a loss function that compares predictions of the model with the matrix;
• compute an inverse of the model representing an inverse of the matrix based on the trained model parameters;
• and
• apply the computed inverse of the model to a noise prone quantum readout of the plurality of qubits of the quantum computer to obtain a substantially noise free quantum readout from the quantum computer.

A classical computer configured to execute a non-transitory computer-executable code, the code when executed by the classical computer causes a quantum computer to:

• perform a plurality of quantum measurements on plurality of qubits having predetermined plurality of states to obtain a plurality of measurement outputs;
• select a model for a matrix linking the predetermined plurality of states to the plurality of measurement outputs, the model having a plurality of model parameters, wherein a number of the plurality of model parameters grows less than exponentially with a number of the plurality of states;
• train the plurality of model parameters to minimize a loss function that compares predictions of the model with the matrix;
• compute an inverse of the model representing an inverse of the matrix based on the trained model parameters;
• and
• apply the computed inverse of the model to a noise prone quantum readout of the plurality of qubits of the quantum computer to obtain a substantially noise free quantum readout from the quantum computer.