Readout Error Mitigation

[justinlietz]

Required prerequisites

• [X] Search the issue tracker to check if your feature has already been mentioned or rejected in other issues.

Describe the feature

Background

Readout errors are caused by imperfect qubit measurement, and are a common source of error in quantum computing. Properly modeling these errors in simulation can give the user tools to better understand how these errors and how to mitigate them when running on actual quantum devices.

There is a large body of work studying readout error, particularly in the context of how to mitigate it [1], [2].

Description

Develop a CUDA-Q application and apply readout error to the measurement results of a sampled CUDA-Q kernel. Next, perform readout error mitigation (REM) on those results. This application can be written in either C++ or Python.

The implementation should include two versions of both the measurement error and the subsequent measurement error mitigation: independent qubit measurement error model and full confusion matrix inversion.

References

[1] https://mitiq.readthedocs.io/en/stable/guide/rem-5-theory.html [2] https://mitiq.readthedocs.io/en/stable/guide/rem-3-options.html