Qiskit-Extensions / qiskit-experiments / 5634793061

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Stark P1 spectroscopy experiment (#1010)

### Summary

This PR adds `StarkP1Spectroscopy` experiment and a dedicated analysis.
User can set amplitudes to scan to run this experiment, and the analysis
class can convert the amplitudes into frequencies if Stark coefficients
are provided. These coefficients can be calibrated with
`StarkRamseyXYAmpScan` experiment introduced in #1009 .

### Details and comments

The test experiment result is available in
[6799e7ae-414f-4816-b887-b4c3ba498624](https://quantum-computing.ibm.com/experiments/6799e7ae-414f-4816-b887-b4c3ba498624).
This experiment result was obtained with the following experiment code:

```python
from qiskit_experiments.library import StarkP1Spectroscopy

exp = StarkP1Spectroscopy((0, ), backend)
exp_data = exp.run().block_for_results()
```

The Stark coefficients can be directly set in the analysis options. By
the default setting, the analysis class searches for the coefficients in
the experiment service. If analysis results for all coefficients are
found (i.e. previously saved in the service), it automatically converts
the amplitudes into frequencies for visualization.

A public class method
`StarkP1SpectAnalysis.retrieve_coefficients_from_service` is also
offered so that a user can set a coefficients dictionary in advance.
This is convenient when the experiment instance is run repeatedly,
because retrieving analysis data from the service causes a communication
overhead. For example,

```python
from qiskit_experiments.library.characterization.analysis import StarkP1SpectAnalysis

# overhead happens only once
coeffs = StarkP1SpectAnalysis.retrieve_coefficients_from_service(
    service=service,
    qubit=0,
    backend=backend.name,
)
exp.analysis.set_options(stark_coefficients=coeffs)

for _ in range(10):
    exp_data = exp.run().block_for_result()
    exp_data.save()
```

User can make a subclass of this analysis class `StarkP1SpectAnalysis`
to perform custom analysis. This built-in class doe... (continued)

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