update documentation for flipping

Merge branch 'pi_half' of github.com:qiboteam/qibocal into pi_half

doc/source/protocols/flipping.rst

@@ -1,16 +1,18 @@
 Flipping
 ========
 
-The flipping experiment corrects the amplitude in the qubit drive pulse. In this experiment,
-we applying an :math:`R_x(\pi/2)` rotation followed by :math:`N` flips (two :math:`R_x(\pi)` rotations)
+The flipping experiment corrects the amplitude in the qubit drive pulse for :math:`R_x(\pi)` rotations. In this experiment,
+we apply an :math:`R_x(\pi/2)` rotation followed by :math:`N` flips (two :math:`R_x(\pi)` rotations)
 and we measure the qubit state.
 The first :math:`R_x(\pi/2)` is necessary to discriminate the over rotations and under rotations of the :math:`R_x(\pi)` pulse:
 without it the difference between the two cases is just a global phase, i.e., the
 probabilities are the same. With the :math:`R_x(\pi/2)` pulse, in case of under rotations the state will be closer to :math:`\ket{0}`
 after the initial flip, in the over rotations one the final state will be closer to :math:`\ket{1}`.
 
 By fitting the resulting data with a sinusoidal function, we can determine the delta amplitude, which allows us to refine the
-:math:`\pi` pulse amplitue.
+:math:`\pi` pulse amplitude.
+
+We implemented also a version of the flipping protocol to calibrate the drive pulse amplitude of the :math:`R_x(\pi/2)` rotations, in this case each :math:`R_x(\pi)` rotation is replaced by two math:`R_x(\pi/2)` rotations.
 
 Parameters
 ^^^^^^^^^^
@@ -35,6 +37,20 @@ The expected output is the following:
 
 .. image:: flipping.png
 
+If the same experiment is run setting the `rx90: True` the flipping is performed to calibrate the amplitude of the :math:`R_x(\pi/2)` rotation
+
+.. code-block:: yaml
+
+	- id: flipping
+	  operation: flipping
+	  parameters:
+	    delta_amplitude: 0.05
+	    nflips_max: 30
+	    nflips_step: 1
+	    rx90: True
+
+The expected output is the following:
+
 Requirements
 ^^^^^^^^^^^^