Add dt to GenericBackendV2 (#13830)

Author: ElePT

qiskit/providers/fake_provider/generic_backend_v2.py

@@ -530,6 +530,7 @@ def __init__(
         control_flow: bool = False,
         calibrate_instructions: bool | InstructionScheduleMap | None = None,
         dtm: float | None = None,
+        dt: float | None = None,
         seed: int | None = None,
         pulse_channels: bool = True,
         noise_info: bool = True,
@@ -579,6 +580,9 @@ def __init__(
             dtm: System time resolution of output signals in nanoseconds.
                 None by default.
 
+            dt: System time resolution of input signals in nanoseconds.
+                None by default.
+
             seed: Optional seed for generation of default values.
 
             pulse_channels: DEPRECATED. If true, sets default pulse channel information on the backend.
@@ -596,6 +600,7 @@ def __init__(
         self._sim = None
         self._rng = np.random.default_rng(seed=seed)
         self._dtm = dtm
+        self._dt = dt
         self._num_qubits = num_qubits
         self._control_flow = control_flow
         self._calibrate_instructions = calibrate_instructions
@@ -788,15 +793,15 @@ def _build_generic_target(self):
             self._target = Target(
                 description=f"Generic Target with {self._num_qubits} qubits",
                 num_qubits=self._num_qubits,
-                dt=properties["dt"],
+                dt=properties["dt"] if self._dt is None else self._dt,
                 qubit_properties=None,
                 concurrent_measurements=[list(range(self._num_qubits))],
             )
         else:
             self._target = Target(
                 description=f"Generic Target with {self._num_qubits} qubits",
                 num_qubits=self._num_qubits,
-                dt=properties["dt"],
+                dt=properties["dt"] if self._dt is None else self._dt,
                 qubit_properties=[
                     QubitProperties(
                         t1=self._rng.uniform(properties["t1"][0], properties["t1"][1]),

releasenotes/notes/add-dt-generic-backend-v2-822f8806517e5dd1.yaml

@@ -0,0 +1,12 @@
+---
+features_providers:
+  - |
+    Added the ability to set the ``dt`` property of :class:`.GenericBackendV2` in the class initializer
+    with a new ``dt`` argument. Example usage::
+
+      from qiskit.providers.fake_provider import GenericBackendV2
+      backend = GenericBackendV2(
+        num_qubits=5, 
+        basis_gates=["cx", "id", "rz", "sx", "x"],
+        dt= 2.22*e-10, 
+        seed=42)

test/python/providers/fake_provider/test_generic_backend_v2.py

@@ -227,3 +227,12 @@ def test_duration_defaults(self):
                     if inst not in ["delay", "reset"]:
                         self.assertGreaterEqual(duration, expected_durations[inst][0])
                         self.assertLessEqual(duration, expected_durations[inst][1])
+
+    def test_custom_dt(self):
+        """Test that the custom dt is respected."""
+
+        ref_backend = GenericBackendV2(num_qubits=2, basis_gates=["cx", "id"], seed=42)
+        double_dt_backend = GenericBackendV2(
+            num_qubits=2, basis_gates=["cx", "id"], dt=ref_backend.dt * 2, seed=42
+        )
+        self.assertEqual(ref_backend.dt * 2, double_dt_backend.dt)