✨ Add Dynamic QFT benchmark

CHANGELOG.md

@@ -11,6 +11,7 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 
 ### Added
 
+- ✨ Add Dynamic QFT benchmark ([#XXX]) ([**@inesalonsoo**])
 - ✨ Add Iterative Quantum Phase Estimation (IQPE) benchmark ([#925]) ([**@johanneswittmann9**])
 
 ### Fixed

src/mqt/bench/benchmarks/dynamic_qft.py

@@ -0,0 +1,43 @@
+# Copyright (c) 2023 - 2026 Chair for Design Automation, TUM
+# Copyright (c) 2025 - 2026 Munich Quantum Software Company GmbH
+# All rights reserved.
+#
+# SPDX-License-Identifier: MIT
+#
+# Licensed under the MIT License
+
+"""Dynamical QFT benchmark definition."""
+
+from __future__ import annotations
+
+import numpy as np
+from qiskit import ClassicalRegister
+from qiskit.circuit import QuantumCircuit, QuantumRegister
+from qiskit.circuit.library import PhaseGate
+
+from ._registry import register_benchmark
+
+
+@register_benchmark("dynamic_qft", description="Dynamic QFT")
+def create_circuit(num_qubits: int) -> QuantumCircuit:
+    """Return a circuit implementing the Dynamic QFT."""
+    if num_qubits < 1:
+        msg = "The number of qubits must be at least 1."
+        raise ValueError(msg)
+
+    q = QuantumRegister(num_qubits, "q")
+    c = ClassicalRegister(num_qubits, "c")
+    qc = QuantumCircuit(q, c, name="dynamic_qft")
+
+    # Forward loop that mirrors the gate order and qubit indices of the static QFT
+    for i in range(num_qubits):
+        qc.h(q[i])
+        qc.measure(q[i], c[i])
+
+        # Apply feed-forward phase corrections to all remaining qubits
+        for j in range(i + 1, num_qubits):
+            angle = np.pi / (2 ** (j - i))
+            p_gate = PhaseGate(angle).c_if(c[i], 1)
+            qc.append(p_gate, [q[j]])
+
+    return qc

tests/test_bench.py

@@ -210,6 +210,7 @@ def test_arithmetic_circuits(benchmark_name: str, input_value: int) -> None:
         ("ae", 1, None, r"Number of qubits must be at least 2 \(1 evaluation \+ 1 target\)."),
         ("shors_nine_qubit_code", 9, None, "num_qubits must be divisible by 17."),
         ("seven_qubit_steane_code", 9, None, "num_qubits must be divisible by 13."),
+        ("dynamic_qft", 0, None, "The number of qubits must be at least 1."),
     ],
 )
 def test_wrong_circuit_size(benchmark_name: str, input_value: int, kind: str | None, msg: str) -> None:
@@ -345,6 +346,19 @@ def test_shors_nine_qubit_code_circuit_structure(num_qubits: int) -> None:
     )
 
 
+@pytest.mark.parametrize("num_qubits", [1, 2, 4, 8])
+def test_dynamic_qft_circuit_structure(num_qubits: int) -> None:
+    """Test that the dynamic QFT allocates registers and compiles."""
+    qc = create_circuit("dynamic_qft", num_qubits)
+
+    assert qc.num_qubits == num_qubits
+    assert qc.name == "dynamic_qft"
+
+    # Verify both a quantum and classical register exist with matching sizes
+    assert len(qc.qregs) == 1
+    assert len(qc.cregs) == 1
+
+
 @pytest.mark.parametrize("num_qubits", [13, 26, 39, 52])
 def test_seven_qubit_steane_code_circuit_structure(num_qubits: int) -> None:
     """Test that Steane 7-qubit code circuits have the expected structure.
@@ -409,7 +423,7 @@ def test_seven_qubit_steane_code_circuit_structure(num_qubits: int) -> None:
             get_target_for_gateset("ionq_forte", num_qubits=5),
             0,
         ),
-        ("qft", BenchmarkLevel.NATIVEGATES, 3, get_target_for_gateset("rigetti", 5), 2),
+        ("dynamic_qft", BenchmarkLevel.NATIVEGATES, 3, get_target_for_gateset("rigetti", 5), 2),
         # Mapped level tests
         (
             "ghz",