qamomile.qiskit.emitters

Qiskit-specific CompositeGate emitters.

This package contains emitters for native Qiskit implementations of composite gates like QFT and IQFT.

Note: QPE (PhaseEstimation) is NOT included here because it’s deprecated in Qiskit 2.1 and will be removed in 3.0. QPE uses manual decomposition.

Overview¶

Classes¶

QiskitQFTEmitter [source]¶

class QiskitQFTEmitter

Emitter for QFT and IQFT using Qiskit’s native library.

Uses qiskit.circuit.library.QFTGate which is the recommended API since Qiskit 2.1. This provides optimized implementations that benefit from Qiskit’s circuit optimization passes.

Supports:

• CompositeGateType.QFT: Quantum Fourier Transform

• CompositeGateType.IQFT: Inverse Quantum Fourier Transform

Methods¶

can_emit¶

def can_emit(self, gate_type: CompositeGateType) -> bool

Check if this emitter can handle the given gate type.

Parameters:

Returns:

bool — True for QFT and IQFT, False otherwise

emit¶

def emit(
    self,
    circuit: 'QuantumCircuit',
    op: CompositeGateOperation,
    qubit_indices: list[int],
    bindings: dict[str, Any],
) -> bool

Emit QFT or IQFT to the circuit using Qiskit’s native library.

Parameters:

Returns:

bool — True if emission succeeded, False to fall back to manual

emit_raw_iqft¶

def emit_raw_iqft(self, circuit: 'QuantumCircuit', qubit_indices: list[int]) -> bool

Emit IQFT directly without CompositeGateOperation.

Used for recursive native emit within other composite gates (e.g., QPE).

Parameters:

Returns:

bool — True if emission succeeded, False to fall back to manual

emit_raw_qft¶

def emit_raw_qft(self, circuit: 'QuantumCircuit', qubit_indices: list[int]) -> bool

Emit QFT directly without CompositeGateOperation.

Used for recursive native emit within other composite gates.

Parameters:

Returns:

bool — True if emission succeeded, False to fall back to manual

qamomile.qiskit.emitters.qft¶

Qiskit QFT/IQFT emitter using native qiskit.circuit.library.QFTGate.

Overview¶

Classes¶

CompositeGateOperation [source]¶

class CompositeGateOperation(Operation)

Represents a composite gate (QPE, QFT, etc.) as a single operation.

CompositeGate allows representing complex multi-gate operations as a single atomic operation in the IR. This enables:

• Resource estimation without full implementation

• Backend-native conversion (e.g., Qiskit’s QPE)

• User-defined complex gates

The operands structure depends on has_implementation:

• If has_implementation=True:

  • operands[0]: BlockValue (the implementation)

  • operands[1:1+num_control_qubits]: Control qubits (if any)

  • operands[1+num_control_qubits:1+num_control_qubits+num_target_qubits]: Target qubits

  • operands[1+num_control_qubits+num_target_qubits:]: Parameters

• If has_implementation=False (stub):

  • operands[0:num_control_qubits]: Control qubits (if any)

  • operands[num_control_qubits:num_control_qubits+num_target_qubits]: Target qubits

  • operands[num_control_qubits+num_target_qubits:]: Parameters

The results structure:

• results[0:num_control_qubits]: Control qubits (returned)

• results[num_control_qubits:]: Target qubits (returned)

Constructor¶

def __init__(
    self,
    operands: list[Value] = list(),
    results: list[Value] = list(),
    gate_type: CompositeGateType = CompositeGateType.CUSTOM,
    num_control_qubits: int = 0,
    num_target_qubits: int = 0,
    custom_name: str = '',
    resource_metadata: ResourceMetadata | None = None,
    has_implementation: bool = True,
    composite_gate_instance: Any = None,
    strategy_name: str | None = None,
) -> None

Attributes¶

• composite_gate_instance: Any

• control_qubits: list[‘Value’] Get the control qubit operands.

• custom_name: str

• gate_type: CompositeGateType

• has_implementation: bool

• implementation: ‘BlockValue | None’ Get the implementation BlockValue, if any.

• name: str Human-readable name of this composite gate.

• num_control_qubits: int

• num_target_qubits: int

• operation_kind: OperationKind Return the operation kind (always QUANTUM).

• parameters: list[‘Value’] Get the parameter operands (angles, etc.).

• resource_metadata: ResourceMetadata | None

• signature: Signature Return the operation signature.

• strategy_name: str | None

• target_qubits: list[‘Value’] Get the target qubit operands.

CompositeGateType [source]¶

class CompositeGateType(enum.Enum)

Registry of known composite gate types.

Attributes¶

• CUSTOM

• IQFT

• QFT

• QPE

QiskitQFTEmitter [source]¶

class QiskitQFTEmitter

Emitter for QFT and IQFT using Qiskit’s native library.

Uses qiskit.circuit.library.QFTGate which is the recommended API since Qiskit 2.1. This provides optimized implementations that benefit from Qiskit’s circuit optimization passes.

Supports:

• CompositeGateType.QFT: Quantum Fourier Transform

• CompositeGateType.IQFT: Inverse Quantum Fourier Transform

Methods¶

can_emit¶

def can_emit(self, gate_type: CompositeGateType) -> bool

Check if this emitter can handle the given gate type.

Parameters:

Returns:

bool — True for QFT and IQFT, False otherwise

emit¶

def emit(
    self,
    circuit: 'QuantumCircuit',
    op: CompositeGateOperation,
    qubit_indices: list[int],
    bindings: dict[str, Any],
) -> bool

Emit QFT or IQFT to the circuit using Qiskit’s native library.

Parameters:

Returns:

bool — True if emission succeeded, False to fall back to manual

emit_raw_iqft¶

def emit_raw_iqft(self, circuit: 'QuantumCircuit', qubit_indices: list[int]) -> bool

Emit IQFT directly without CompositeGateOperation.

Used for recursive native emit within other composite gates (e.g., QPE).

Parameters:

Returns:

bool — True if emission succeeded, False to fall back to manual

emit_raw_qft¶

def emit_raw_qft(self, circuit: 'QuantumCircuit', qubit_indices: list[int]) -> bool

Emit QFT directly without CompositeGateOperation.

Used for recursive native emit within other composite gates.

Parameters:

Returns:

bool — True if emission succeeded, False to fall back to manual