Add benchmarks to user guide

[nathanshammah]

Issue Description

Benchmark quantum circuit are a crucial ingredient to test empirically the performance of quantum error mitigation techniques on real or simulated devices, and can be used as a diagnostic tool when designing new techniques or modifying existing ones. They are also used in the calibrator. While some benchmarks are quite well known, as randomized benchmarking or GHZ, others have been proposed more recently, like quantum volume circuits and mirror quantum circuits.

Mitiq provides a comprehensive list of quantum circuits that can be used for benchmarks and they are listed in the API doc. However, their usage may require some additional background information. Moreover, they can be of use for several tutorials and to get started with Mitiq.

Proposed Solution

I propose to add a section in the documentation, in the user guide, under the core concepts, listing the various quantum circuits present in the benchmarks, with some details and code blocks, and useful references.

Additional References

• https://mitiq.readthedocs.io/en/latest/apidoc.html#benchmarks
• https://arxiv.org/abs/2210.07194

[nathanshammah]

@FarLab I'd be happy to work on this, it could even make it into this milestone.