Add qubit_attributes to GridDeviceMetadata and corresponding proto

cirq-core/cirq/devices/grid_device_metadata.py

@@ -17,7 +17,7 @@
 from __future__ import annotations
 
 from collections.abc import Iterable, Mapping
-from typing import cast, TYPE_CHECKING
+from typing import Any, cast, TYPE_CHECKING
 
 import networkx as nx
 
@@ -39,6 +39,7 @@ def __init__(
         gate_durations: Mapping[cirq.GateFamily, cirq.Duration] | None = None,
         all_qubits: Iterable[cirq.GridQubit] | None = None,
         compilation_target_gatesets: Iterable[cirq.CompilationTargetGateset] = (),
+        qubit_attributes: Mapping[cirq.GridQubit, Mapping[str, Any]] | None = None,
     ):
         """Create a GridDeviceMetadata object.
 
@@ -117,6 +118,11 @@ def __init__(
                 )
 
         self._gate_durations = gate_durations
+        self._qubit_attributes = (
+            {q: dict(attrs) for q, attrs in qubit_attributes.items()}
+            if qubit_attributes is not None
+            else {}
+        )
 
     @property
     def qubit_set(self) -> frozenset[cirq.GridQubit]:
@@ -175,25 +181,37 @@ def gate_durations(self) -> Mapping[cirq.GateFamily, cirq.Duration] | None:
 
         return self._gate_durations
 
+    @property
+    def qubit_attributes(self) -> Mapping[cirq.GridQubit, Mapping[str, Any]]:
+        """Returns a mapping from qubit to its attributes (if applicable)."""
+        return self._qubit_attributes
+
     def _value_equality_values_(self):
         duration_equality = ''
         if self._gate_durations is not None:
             duration_equality = sorted(self._gate_durations.items(), key=lambda x: repr(x[0]))
 
+        attributes_equality = sorted(
+            [(q, tuple(sorted(attrs.items()))) for q, attrs in self._qubit_attributes.items()],
+            key=lambda x: x[0],
+        )
+
         return (
             self._qubit_pairs,
             self._gateset,
             tuple(duration_equality),
             tuple(sorted(self.qubit_set)),
             frozenset(self._compilation_target_gatesets),
+            tuple(attributes_equality),
         )
 
     def __repr__(self) -> str:
         qubit_pair_tuples = frozenset({tuple(sorted(p)) for p in self._qubit_pairs})
         return (
             f'cirq.GridDeviceMetadata({repr(qubit_pair_tuples)},'
             f' {repr(self._gateset)}, {repr(self._gate_durations)},'
-            f' {repr(self.qubit_set)}, {repr(self._compilation_target_gatesets)})'
+            f' {repr(self.qubit_set)}, {repr(self._compilation_target_gatesets)},'
+            f' {repr(self._qubit_attributes)})'
         )
 
     def _json_dict_(self):
@@ -207,6 +225,10 @@ def _json_dict_(self):
             'gate_durations': duration_payload,
             'all_qubits': sorted(self.qubit_set),
             'compilation_target_gatesets': list(self._compilation_target_gatesets),
+            'qubit_attributes': sorted(
+                [(q, sorted(attrs.items())) for q, attrs in self._qubit_attributes.items()],
+                key=lambda x: x[0],
+            ),
         }
 
     @classmethod
@@ -217,6 +239,7 @@ def _from_json_dict_(
         gate_durations,
         all_qubits,
         compilation_target_gatesets=(),
+        qubit_attributes=None,
         **kwargs,
     ):
         return cls(
@@ -225,4 +248,5 @@ def _from_json_dict_(
             dict(gate_durations) if gate_durations is not None else None,
             all_qubits,
             compilation_target_gatesets,
+            dict(qubit_attributes) if qubit_attributes is not None else None,
         )

cirq-core/cirq/devices/grid_device_metadata_test.py

@@ -16,6 +16,8 @@
 
 from __future__ import annotations
 
+from typing import Any
+
 import networkx as nx
 import pytest
 
@@ -202,3 +204,43 @@ def test_repr() -> None:
         compilation_target_gatesets=target_gatesets,
     )
     cirq.testing.assert_equivalent_repr(metadata)
+
+
+def test_griddevice_metadata_qubit_attributes() -> None:
+    qubits = cirq.GridQubit.rect(1, 2)
+    gateset = cirq.Gateset(cirq.XPowGate)
+    qubit_attributes: dict[cirq.GridQubit, dict[str, Any]] = {
+        cirq.GridQubit(0, 0): {"type": "transmon", "frequency": 5.1},
+        cirq.GridQubit(0, 1): {"index": 42},
+    }
+
+    metadata = cirq.GridDeviceMetadata(
+        qubit_pairs=[], gateset=gateset, all_qubits=qubits, qubit_attributes=qubit_attributes
+    )
+
+    assert metadata.qubit_attributes == qubit_attributes
+
+    # test JSON serialization
+    rep_str = cirq.to_json(metadata)
+    assert metadata == cirq.read_json(json_text=rep_str)
+
+    # test repr
+    cirq.testing.assert_equivalent_repr(metadata)
+
+    # test equality
+    qubit_attributes2: dict[cirq.GridQubit, dict[str, Any]] = {
+        cirq.GridQubit(0, 0): {"type": "transmon", "frequency": 5.1},
+        cirq.GridQubit(0, 1): {"index": 43},  # different index
+    }
+    metadata2 = cirq.GridDeviceMetadata(
+        qubit_pairs=[], gateset=gateset, all_qubits=qubits, qubit_attributes=qubit_attributes2
+    )
+
+    metadata3 = cirq.GridDeviceMetadata(
+        qubit_pairs=[], gateset=gateset, all_qubits=qubits, qubit_attributes=None
+    )
+
+    eq = cirq.testing.EqualsTester()
+    eq.add_equality_group(metadata)
+    eq.add_equality_group(metadata2)
+    eq.add_equality_group(metadata3)

cirq-core/cirq/protocols/json_test_data/GridDeviceMetadata.json

@@ -265,5 +265,6 @@
       "required_sqrt_iswap_count": null,
       "use_sqrt_iswap_inv": false
     }
-  ]
+  ],
+  "qubit_attributes": []
 }

cirq-core/cirq/protocols/json_test_data/GridDeviceMetadata.repr

@@ -1 +1 @@
-cirq.GridDeviceMetadata(frozenset({(cirq.GridQubit(1, 1), cirq.GridQubit(1, 2)), (cirq.GridQubit(0, 0), cirq.GridQubit(1, 0)), (cirq.GridQubit(1, 0), cirq.GridQubit(1, 1)), (cirq.GridQubit(0, 1), cirq.GridQubit(1, 1)), (cirq.GridQubit(0, 0), cirq.GridQubit(0, 1)), (cirq.GridQubit(0, 2), cirq.GridQubit(1, 2)), (cirq.GridQubit(0, 1), cirq.GridQubit(0, 2))}), cirq.Gateset(cirq.ops.common_gates.XPowGate, cirq.ops.common_gates.YPowGate, cirq.ops.common_gates.ZPowGate, cirq.CZ, (cirq.ISWAP**0.5), unroll_circuit_op = True), {cirq.GateFamily(gate=cirq.ops.common_gates.XPowGate, ignore_global_phase=True, tags_to_accept=frozenset(), tags_to_ignore=frozenset()): cirq.Duration(nanos=1), cirq.GateFamily(gate=cirq.ops.common_gates.YPowGate, ignore_global_phase=True, tags_to_accept=frozenset(), tags_to_ignore=frozenset()): cirq.Duration(picos=1), cirq.GateFamily(gate=cirq.ops.common_gates.ZPowGate, ignore_global_phase=True, tags_to_accept=frozenset(), tags_to_ignore=frozenset()): cirq.Duration(picos=1), cirq.GateFamily(gate=cirq.CZ, ignore_global_phase=True, tags_to_accept=frozenset(), tags_to_ignore=frozenset()): cirq.Duration(picos=500), cirq.GateFamily(gate=(cirq.ISWAP**0.5), ignore_global_phase=True, tags_to_accept=frozenset(), tags_to_ignore=frozenset()): cirq.Duration(picos=600)}, frozenset({cirq.GridQubit(1, 0), cirq.GridQubit(0, 2), cirq.GridQubit(9, 9), cirq.GridQubit(10, 10), cirq.GridQubit(0, 1), cirq.GridQubit(1, 1), cirq.GridQubit(0, 0), cirq.GridQubit(1, 2)}), (cirq.CZTargetGateset(atol=1e-08, allow_partial_czs=False), cirq.SqrtIswapTargetGateset(atol=1e-08, required_sqrt_iswap_count=None, use_sqrt_iswap_inv=False)))
+cirq.GridDeviceMetadata(frozenset({(cirq.GridQubit(1, 1), cirq.GridQubit(1, 2)), (cirq.GridQubit(0, 0), cirq.GridQubit(1, 0)), (cirq.GridQubit(1, 0), cirq.GridQubit(1, 1)), (cirq.GridQubit(0, 1), cirq.GridQubit(1, 1)), (cirq.GridQubit(0, 0), cirq.GridQubit(0, 1)), (cirq.GridQubit(0, 2), cirq.GridQubit(1, 2)), (cirq.GridQubit(0, 1), cirq.GridQubit(0, 2))}), cirq.Gateset(cirq.ops.common_gates.XPowGate, cirq.ops.common_gates.YPowGate, cirq.ops.common_gates.ZPowGate, cirq.CZ, (cirq.ISWAP**0.5), unroll_circuit_op = True), {cirq.GateFamily(gate=cirq.ops.common_gates.XPowGate, ignore_global_phase=True, tags_to_accept=frozenset(), tags_to_ignore=frozenset()): cirq.Duration(nanos=1), cirq.GateFamily(gate=cirq.ops.common_gates.YPowGate, ignore_global_phase=True, tags_to_accept=frozenset(), tags_to_ignore=frozenset()): cirq.Duration(picos=1), cirq.GateFamily(gate=cirq.ops.common_gates.ZPowGate, ignore_global_phase=True, tags_to_accept=frozenset(), tags_to_ignore=frozenset()): cirq.Duration(picos=1), cirq.GateFamily(gate=cirq.CZ, ignore_global_phase=True, tags_to_accept=frozenset(), tags_to_ignore=frozenset()): cirq.Duration(picos=500), cirq.GateFamily(gate=(cirq.ISWAP**0.5), ignore_global_phase=True, tags_to_accept=frozenset(), tags_to_ignore=frozenset()): cirq.Duration(picos=600)}, frozenset({cirq.GridQubit(1, 0), cirq.GridQubit(0, 2), cirq.GridQubit(9, 9), cirq.GridQubit(10, 10), cirq.GridQubit(0, 1), cirq.GridQubit(1, 1), cirq.GridQubit(0, 0), cirq.GridQubit(1, 2)}), (cirq.CZTargetGateset(atol=1e-08, allow_partial_czs=False), cirq.SqrtIswapTargetGateset(atol=1e-08, required_sqrt_iswap_count=None, use_sqrt_iswap_inv=False)), {})

cirq-google/cirq_google/api/v2/device.proto

@@ -34,6 +34,9 @@ message DeviceSpecification {
   // are advice to users of the device, specified in English text
   // For instance, "All Z gates are converted to VirtualZ gates".
   string developer_recommendations = 4;
+
+  // Qubit attributes for the device.
+  repeated QubitAttributes qubit_attributes = 6;
 }
 
 // This contains information about a single device gate.
@@ -199,3 +202,25 @@ message Target {
   // A list of qubit ids that form a valid gate target.
   repeated string ids = 1;
 }
+
+// Qubit attributes for a specific qubit.
+message QubitAttributes {
+  string qubit = 1;
+  repeated QubitAttributeEntry attributes = 2;
+}
+
+// A key-value entry representing a single qubit attribute.
+message QubitAttributeEntry {
+  string name = 1;
+  QubitAttributeValue value = 2;
+}
+
+// A generic value for a qubit attribute.
+message QubitAttributeValue {
+  oneof val {
+    string string_value = 1;
+    int64 int_value = 2;
+    double double_value = 3;
+    bool bool_value = 4;
+  }
+}