Adding a bunch of gates from the lab

[arsalan-motamedi]

Context:
There are many interesting things implemented in the old lab which are still missing in lab_dev.

Description of the Change:
We add the following gates:

• Pgate: the quadratic phase gate
• CXgate and CZgate: the controlled-X and -Z gates
• MZgate: Mach-Zehnder gate
• Interferometer and RealInterferometer

Also, we add the BargmannEigenstate which are simply unnormalized coherent states.

Benefits:
More things to have ready!

Possible Drawbacks:
None.

Related GitHub Issues:
None.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 90.16%. Comparing base (4c603d0) to head (babcd2e).
Report is 1 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop     #520      +/-   ##
===========================================
+ Coverage    89.84%   90.16%   +0.31%     
===========================================
  Files           93      101       +8     
  Lines         6098     6291     +193     
===========================================
+ Hits          5479     5672     +193     
  Misses         619      619              

Files with missing lines	Coverage Δ
mrmustard/lab_dev/states/__init__.py	100.00% <100.00%> (ø)
mrmustard/lab_dev/states/bargmann_eigenstate.py	100.00% <100.00%> (ø)
mrmustard/lab_dev/states/gstate.py	100.00% <100.00%> (ø)
mrmustard/lab_dev/states/ket.py	98.59% <ø> (ø)
mrmustard/lab_dev/transformations/__init__.py	100.00% <100.00%> (ø)
mrmustard/lab_dev/transformations/cxgate.py	100.00% <100.00%> (ø)
mrmustard/lab_dev/transformations/czgate.py	100.00% <100.00%> (ø)
mrmustard/lab_dev/transformations/ggate.py	100.00% <100.00%> (ø)
...rmustard/lab_dev/transformations/interferometer.py	100.00% <100.00%> (ø)
mrmustard/lab_dev/transformations/mzgate.py	100.00% <100.00%> (ø)
... and 9 more

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[apchytr]

Some initial comments. Thanks Arsalan!

[Rahps97]

Hi,
Sorry for a newbie question. I was looking for a Kerr gate (need to implement non-linear operation). Any suggestions?

[arsalan-motamedi]

Hi, Sorry for a newbie question. I was looking for a Kerr gate (need to implement non-linear operation). Any suggestions?

Thank you for the question. We are working to add a Unitary.from_fock() method which can be used to initialize a Kerr gate.