add spinful givens ansatz operator gate

python/ffsim/qiskit/__init__.py

@@ -14,6 +14,7 @@
 
 from ffsim.qiskit.gates import (
     DiagCoulombEvolutionJW,
+    GivensAnsatzOperatorJW,
     GivensAnsatzOperatorSpinlessJW,
     OrbitalRotationJW,
     OrbitalRotationSpinlessJW,
@@ -38,6 +39,7 @@
 __all__ = [
     "DiagCoulombEvolutionJW",
     "DropNegligible",
+    "GivensAnsatzOperatorJW",
     "GivensAnsatzOperatorSpinlessJW",
     "MergeOrbitalRotations",
     "OrbitalRotationJW",

python/ffsim/qiskit/gates/__init__.py

@@ -11,7 +11,10 @@
 """Qiskit fermionic quantum gates."""
 
 from ffsim.qiskit.gates.diag_coulomb import DiagCoulombEvolutionJW
-from ffsim.qiskit.gates.givens_ansatz import GivensAnsatzOperatorSpinlessJW
+from ffsim.qiskit.gates.givens_ansatz import (
+    GivensAnsatzOperatorJW,
+    GivensAnsatzOperatorSpinlessJW,
+)
 from ffsim.qiskit.gates.orbital_rotation import (
     OrbitalRotationJW,
     OrbitalRotationSpinlessJW,
@@ -26,6 +29,7 @@
 
 __all__ = [
     "DiagCoulombEvolutionJW",
+    "GivensAnsatzOperatorJW",
     "GivensAnsatzOperatorSpinlessJW",
     "OrbitalRotationJW",
     "OrbitalRotationSpinlessJW",

python/ffsim/qiskit/gates/givens_ansatz.py

@@ -28,12 +28,46 @@
 from ffsim.variational import GivensAnsatzOperator
 
 
-class GivensAnsatzOperatorSpinlessJW(Gate):
+class GivensAnsatzOperatorJW(Gate):
     """Givens rotation ansatz operator under the Jordan-Wigner transformation.
 
     See :class:`ffsim.GivensAnsatzOperator` for a description of this gate's unitary.
     """
 
+    def __init__(
+        self, givens_ansatz_operator: GivensAnsatzOperator, *, label: str | None = None
+    ):
+        """Create a new Givens ansatz operator gate.
+
+        Args:
+            givens_ansatz_operator: The Givens rotation ansatz operator.
+            label: The label of the gate.
+        """
+        self.givens_ansatz_operator = givens_ansatz_operator
+        super().__init__(
+            "givens_ansatz_jw", 2 * givens_ansatz_operator.norb, [], label=label
+        )
+
+    def _define(self):
+        """Gate decomposition."""
+        qubits = QuantumRegister(self.num_qubits)
+        circuit = QuantumCircuit(qubits, name=self.name)
+        norb = len(qubits) // 2
+        alpha_qubits = qubits[:norb]
+        beta_qubits = qubits[norb:]
+        for instruction in _givens_ansatz_jw(alpha_qubits, self.givens_ansatz_operator):
+            circuit.append(instruction)
+        for instruction in _givens_ansatz_jw(beta_qubits, self.givens_ansatz_operator):
+            circuit.append(instruction)
+        self.definition = circuit
+
+
+class GivensAnsatzOperatorSpinlessJW(Gate):
+    """Givens rotation ansatz operator under the Jordan-Wigner transformation, spinless.
+
+    Like :class:`GivensAnsatzOperatorJW` but only acts on a single spin species.
+    """
+
     def __init__(
         self, givens_ansatz_operator: GivensAnsatzOperator, *, label: str | None = None
     ):
@@ -52,7 +86,9 @@ def _define(self):
         """Gate decomposition."""
         qubits = QuantumRegister(self.num_qubits)
         self.definition = QuantumCircuit.from_instructions(
-            _givens_ansatz_jw(qubits, self.givens_ansatz_operator), qubits=qubits
+            _givens_ansatz_jw(qubits, self.givens_ansatz_operator),
+            qubits=qubits,
+            name=self.name,
         )
 
 

tests/python/qiskit/givens_ansatz_test.py

@@ -25,14 +25,43 @@ def brickwork(norb: int, n_layers: int):
             yield (j, j + 1)
 
 
-@pytest.mark.parametrize("norb, nocc", ffsim.testing.generate_norb_nocc(range(5)))
-def test_random_givens_ansatz_operator(norb: int, nocc: int):
+@pytest.mark.parametrize("norb, nelec", ffsim.testing.generate_norb_nelec(range(5)))
+def test_random_givens_ansatz_operator_spinful(norb: int, nelec: tuple[int, int]):
     """Test random Givens rotation ansatz gives correct output state."""
     rng = np.random.default_rng()
+    dim = ffsim.dim(norb, nelec)
+    for _ in range(3):
+        n_layers = 2 * norb
+        interaction_pairs = list(brickwork(norb, n_layers))
+        thetas = rng.uniform(-np.pi, np.pi, size=len(interaction_pairs))
+        givens_ansatz_op = ffsim.GivensAnsatzOperator(norb, interaction_pairs, thetas)
+        gate = ffsim.qiskit.GivensAnsatzOperatorJW(givens_ansatz_op)
+
+        small_vec = ffsim.random.random_statevector(dim, seed=rng)
+        big_vec = ffsim.qiskit.ffsim_vec_to_qiskit_vec(
+            small_vec, norb=norb, nelec=nelec
+        )
+
+        statevec = Statevector(big_vec).evolve(gate)
+        result = ffsim.qiskit.qiskit_vec_to_ffsim_vec(
+            np.array(statevec), norb=norb, nelec=nelec
+        )
+
+        expected = ffsim.apply_unitary(
+            small_vec, givens_ansatz_op, norb=norb, nelec=nelec
+        )
+
+        np.testing.assert_allclose(result, expected)
+
+
+@pytest.mark.parametrize("norb, nocc", ffsim.testing.generate_norb_nocc(range(5)))
+def test_random_givens_ansatz_operator_spinless(norb: int, nocc: int):
+    """Test random spinless Givens rotation ansatz gives correct output state."""
+    rng = np.random.default_rng()
     nelec = (nocc, 0)
     dim = ffsim.dim(norb, nelec)
     for _ in range(3):
-        n_layers = norb
+        n_layers = 2 * norb
         interaction_pairs = list(brickwork(norb, n_layers))
         thetas = rng.uniform(-np.pi, np.pi, size=len(interaction_pairs))
         givens_ansatz_op = ffsim.GivensAnsatzOperator(norb, interaction_pairs, thetas)