Explicit adjoints for basic_gates.rotation bloqs (#881)

qualtran/bloqs/basic_gates/rotation.py

@@ -11,10 +11,10 @@
 #  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 #  See the License for the specific language governing permissions and
 #  limitations under the License.
-
 from functools import cached_property
 from typing import Protocol, Union
 
+import attrs
 import cirq
 import numpy as np
 import sympy
@@ -88,6 +88,9 @@ def __pow__(self, power):
         g = self.cirq_gate**power
         return ZPowGate(g.exponent, g.global_shift, self.eps)
 
+    def adjoint(self) -> 'ZPowGate':
+        return attrs.evolve(self, exponent=-self.exponent)
+
 
 @bloq_example
 def _z_pow() -> ZPowGate:
@@ -120,6 +123,9 @@ def __pow__(self, power):
         g = self.cirq_gate**power
         return CZPowGate(g.exponent, g.global_shift, self.eps)
 
+    def adjoint(self) -> 'CZPowGate':
+        return attrs.evolve(self, exponent=-self.exponent)
+
 
 @frozen
 class XPowGate(CirqGateAsBloqBase):
@@ -173,6 +179,9 @@ def decompose_bloq(self) -> 'CompositeBloq':
     def cirq_gate(self) -> cirq.Gate:
         return cirq.XPowGate(exponent=self.exponent, global_shift=self.global_shift)
 
+    def adjoint(self) -> 'XPowGate':
+        return attrs.evolve(self, exponent=-self.exponent)
+
 
 @bloq_example
 def _x_pow() -> XPowGate:
@@ -235,6 +244,9 @@ def decompose_bloq(self) -> 'CompositeBloq':
     def cirq_gate(self) -> cirq.Gate:
         return cirq.YPowGate(exponent=self.exponent, global_shift=self.global_shift)
 
+    def adjoint(self) -> 'YPowGate':
+        return attrs.evolve(self, exponent=-self.exponent)
+
 
 @bloq_example
 def _y_pow() -> YPowGate:
@@ -274,6 +286,9 @@ def decompose_bloq(self) -> 'CompositeBloq':
     def cirq_gate(self) -> cirq.Gate:
         return cirq.rz(self.angle)
 
+    def adjoint(self) -> 'Rz':
+        return attrs.evolve(self, angle=-self.angle)
+
 
 @frozen
 class Rx(CirqGateAsBloqBase):
@@ -287,6 +302,9 @@ def decompose_bloq(self) -> 'CompositeBloq':
     def cirq_gate(self) -> cirq.Gate:
         return cirq.rx(self.angle)
 
+    def adjoint(self) -> 'Rx':
+        return attrs.evolve(self, angle=-self.angle)
+
 
 @frozen
 class Ry(CirqGateAsBloqBase):
@@ -300,6 +318,9 @@ def decompose_bloq(self) -> 'CompositeBloq':
     def cirq_gate(self) -> cirq.Gate:
         return cirq.ry(self.angle)
 
+    def adjoint(self) -> 'Ry':
+        return attrs.evolve(self, angle=-self.angle)
+
 
 @bloq_example
 def _rx() -> Rx:

qualtran/bloqs/basic_gates/rotation_test.py

@@ -14,10 +14,11 @@
 
 import cirq
 import numpy as np
+import pytest
 from cirq.ops import SimpleQubitManager
 
 from qualtran._infra.gate_with_registers import get_named_qubits
-from qualtran.bloqs.basic_gates import Rx, Ry, Rz, XPowGate, YPowGate, ZPowGate
+from qualtran.bloqs.basic_gates import CZPowGate, Rx, Ry, Rz, XPowGate, YPowGate, ZPowGate
 from qualtran.bloqs.basic_gates.rotation import _rx, _ry, _rz
 
 
@@ -29,6 +30,19 @@ def test_rotation_gates():
     assert Rz(angle).t_complexity().t_incl_rotations() == 1
 
 
+@pytest.mark.parametrize(
+    "bloq",
+    [Rx(0.01), Ry(0.01), Rz(0.01), ZPowGate(0.01), YPowGate(0.01), XPowGate(0.01), CZPowGate(0.01)],
+)
+def test_rotation_gates_adjoint(bloq):
+    assert type(bloq) == type(bloq.adjoint())
+    np.testing.assert_allclose(
+        bloq.tensor_contract() @ bloq.adjoint().tensor_contract(),
+        np.identity(2 ** bloq.signature.n_qubits()),
+        atol=1e-8,
+    )
+
+
 def test_as_cirq_op():
     bloq = Rx(angle=np.pi / 4.0, eps=1e-8)
     quregs = get_named_qubits(bloq.signature.lefts())