added RX90 native gate and modified R method

src/qibolab/_core/native.py

@@ -66,6 +66,8 @@ class SingleQubitNatives(NativeContainer):
 
     RX: Optional[Native] = None
     """Pulse to drive the qubit from state 0 to state 1."""
+    RX90: Optional[Native] = None
+    """Pulse to drive the qubit from state 0 to state +"""
     RX12: Optional[Native] = None
     """Pulse to drive to qubit from state 1 to state 2."""
     MZ: Optional[Native] = None
@@ -78,8 +80,11 @@ def R(self, theta: float = np.pi, phi: float = 0.0) -> PulseSequence:
 
         ``theta`` will be the angle of the rotation, while ``phi`` the angle that the rotation axis forms with x axis.
         """
-        assert self.RX is not None
-        return rotation(self.RX, theta, phi)
+        if self.RX90 != None:
+            return rotation(self.RX, 2 * theta, phi)
+        else:
+            assert self.RX is not None
+            return rotation(self.RX, theta, phi)
 
 
 class TwoQubitNatives(NativeContainer):