Fix typing of initial state in EmulatorConfig, fix normalization with…

… qutip 5 (#792)

* Delete no-normalization output

* Normalize initial state

* Bump to v1.2.1

VERSION.txt

@@ -1 +1 @@
-1.2.0
+1.2.1

pulser-core/pulser/backend/config.py

@@ -76,7 +76,9 @@ class EmulatorConfig(BackendConfig):
 
     sampling_rate: float = 1.0
     evaluation_times: float | Sequence[float] | EVAL_TIMES_LITERAL = "Full"
-    initial_state: Literal["all-ground"] | Sequence[complex] = "all-ground"
+    initial_state: Literal["all-ground"] | Sequence[complex] | np.ndarray = (
+        "all-ground"
+    )
     with_modulation: bool = False
     prefer_device_noise_model: bool = False
     noise_model: NoiseModel = field(default_factory=NoiseModel)

pulser-simulation/pulser_simulation/simulation.py

@@ -348,7 +348,9 @@ def set_initial_state(
                     "Incompatible shape of initial state."
                     + f"Expected {legal_shape}, got {shape}."
                 )
-            self._initial_state = qutip.Qobj(state, dims=legal_dims).to("CSR")
+            self._initial_state = (
+                qutip.Qobj(state, dims=legal_dims).unit().to("CSR")
+            )
 
     @property
     def evaluation_times(self) -> np.ndarray:

tests/test_simulation.py

@@ -1639,3 +1639,36 @@ def pos_factor(qid):
         )
     # Drawing with modulation
     sim.draw()
+
+
+def test_initial_state_sim():
+    seq = Sequence(
+        Register({"q0": (-6, 0), "q1": (0, 0), "q2": (6, 0)}), AnalogDevice
+    )
+    seq.declare_channel("ising", "rydberg_global")
+    seq.add(Pulse.ConstantPulse(4000, 9.28, 18.7, 0), "ising")
+    L = len(seq.register.qubits)
+    initial_state = np.ones(2**L)
+    emulator = QutipEmulator.from_sequence(seq)
+    emulator.set_initial_state(initial_state)
+    np.random.seed(123)
+    res = emulator.run()
+    final_state = res.get_final_state()
+    assert np.all(
+        np.isclose(
+            final_state.full(),
+            np.array(
+                [
+                    [0.28985369 + 0.13530479j],
+                    [0.40220557 + 0.0j],
+                    [0.27445983 + 0.15541026j],
+                    [0.29608403 + 0.06155379j],
+                    [0.40220557 + 0.0j],
+                    [0.36173532 - 0.01617572j],
+                    [0.29608403 + 0.06155379j],
+                    [0.36931122 - 0.15570528j],
+                ]
+            ),
+            1e-2,
+        )
+    )