diff --git a/quick/circuit/circuit.py b/quick/circuit/circuit.py
index b0de8e0..80ac95e 100644
--- a/quick/circuit/circuit.py
+++ b/quick/circuit/circuit.py
@@ -536,7 +536,7 @@ def _gate_mapping(
             self,
             gate: GATES,
             target_indices: int | Sequence[int],
-            control_indices: int | Sequence[int] = [],
+            control_indices: int | Sequence[int] | None = None,
             angles: Sequence[float] = (0, 0, 0)
         ) -> None:
         """ Apply a gate to the circuit.
@@ -551,7 +551,7 @@ def _gate_mapping(
             The gate to apply to the circuit.
         `target_indices` : int | Sequence[int]
             The index of the target qubit(s).
-        `control_indices` : int | Sequence[int], optional, default=[]
+        `control_indices` : int | Sequence[int], optional, default=None
             The index of the control qubit(s).
         `angles` : Sequence[float], optional, default=(0, 0, 0)
             The rotation angles in radians.
diff --git a/quick/circuit/cirqcircuit.py b/quick/circuit/cirqcircuit.py
index ec49b23..69123ff 100644
--- a/quick/circuit/cirqcircuit.py
+++ b/quick/circuit/cirqcircuit.py
@@ -159,12 +159,16 @@ def _gate_mapping(
             self,
             gate: GATES,
             target_indices: int | Sequence[int],
-            control_indices: int | Sequence[int] = [],
+            control_indices: int | Sequence[int] | None = None,
             angles: Sequence[float] = (0, 0, 0)
         ) -> None:
 
         targets = [target_indices] if isinstance(target_indices, int) else list(target_indices)
-        controls = [control_indices] if isinstance(control_indices, int) else list(control_indices)
+
+        if control_indices is None:
+            controls: list[int] = []
+        else:
+            controls = [control_indices] if isinstance(control_indices, int) else list(control_indices)
 
         # Given Cirq uses MSB convention, we will explicitly
         # convert the qubit indices to LSB convention
diff --git a/quick/circuit/pennylanecircuit.py b/quick/circuit/pennylanecircuit.py
index fc75bee..c5f79cf 100644
--- a/quick/circuit/pennylanecircuit.py
+++ b/quick/circuit/pennylanecircuit.py
@@ -128,12 +128,16 @@ def _gate_mapping(
             self,
             gate: GATES,
             target_indices: int | Sequence[int],
-            control_indices: int | Sequence[int] = [],
+            control_indices: int | Sequence[int] | None = None,
             angles: Sequence[float] = (0, 0, 0)
         ) -> None:
 
         targets = [target_indices] if isinstance(target_indices, int) else list(target_indices)
-        controls = [control_indices] if isinstance(control_indices, int) else list(control_indices)
+
+        if control_indices is None:
+            controls: list[int] = []
+        else:
+            controls = [control_indices] if isinstance(control_indices, int) else list(control_indices)
 
         # Given Pennylane uses MSB convention, we will explicitly
         # convert the qubit indices to LSB convention
diff --git a/quick/circuit/qiskitcircuit.py b/quick/circuit/qiskitcircuit.py
index d795454..c091b37 100644
--- a/quick/circuit/qiskitcircuit.py
+++ b/quick/circuit/qiskitcircuit.py
@@ -137,23 +137,27 @@ def _gate_mapping(
             self,
             gate: GATES,
             target_indices: int | Sequence[int],
-            control_indices: int | Sequence[int] = [],
+            control_indices: int | Sequence[int] | None = None,
             angles: Sequence[float] = (0, 0, 0)
         ) -> None:
 
-        target_indices = [target_indices] if isinstance(target_indices, int) else target_indices
-        control_indices = [control_indices] if isinstance(control_indices, int) else control_indices
+        targets = [target_indices] if isinstance(target_indices, int) else list(target_indices)
+
+        if control_indices is None:
+            controls: list[int] = []
+        else:
+            controls = [control_indices] if isinstance(control_indices, int) else list(control_indices)
 
         # Lazily extract the value of the gate from the mapping to avoid
         # creating all the gates at once, and to maintain the abstraction
         gate_operation = self.gate_mapping[gate](angles)
 
-        if control_indices:
-            for target_index in target_indices:
-                self.circuit.append(gate_operation.control(len(control_indices)), [*control_indices[:], target_index])
+        if controls:
+            for target_index in targets:
+                self.circuit.append(gate_operation.control(len(controls)), [*controls[:], target_index])
             return
 
-        for target_index in target_indices:
+        for target_index in targets:
             self.circuit.append(gate_operation, [target_index])
 
     def GlobalPhase(
diff --git a/quick/circuit/quimbcircuit.py b/quick/circuit/quimbcircuit.py
index f1119b1..f9b448d 100644
--- a/quick/circuit/quimbcircuit.py
+++ b/quick/circuit/quimbcircuit.py
@@ -129,12 +129,16 @@ def _gate_mapping(
             self,
             gate: GATES,
             target_indices: int | Sequence[int],
-            control_indices: int | Sequence[int] = [],
+            control_indices: int | Sequence[int] | None = None,
             angles: Sequence[float] = (0, 0, 0)
         ) -> None:
 
         targets = [target_indices] if isinstance(target_indices, int) else list(target_indices)
-        controls = [control_indices] if isinstance(control_indices, int) else list(control_indices)
+
+        if control_indices is None:
+            controls: list[int] = []
+        else:
+            controls = [control_indices] if isinstance(control_indices, int) else list(control_indices)
 
         # Given Quimb uses MSB convention, we will explicitly
         # convert the qubit indices to LSB convention
diff --git a/quick/circuit/tketcircuit.py b/quick/circuit/tketcircuit.py
index 111948f..be61183 100644
--- a/quick/circuit/tketcircuit.py
+++ b/quick/circuit/tketcircuit.py
@@ -130,12 +130,16 @@ def _gate_mapping(
             self,
             gate: GATES,
             target_indices: int | Sequence[int],
-            control_indices: int | Sequence[int] = [],
+            control_indices: int | Sequence[int] | None = None,
             angles: Sequence[float] = (0, 0, 0)
         ) -> None:
 
         targets = [target_indices] if isinstance(target_indices, int) else list(target_indices)
-        controls = [control_indices] if isinstance(control_indices, int) else list(control_indices)
+
+        if control_indices is None:
+            controls: list[int] = []
+        else:
+            controls = [control_indices] if isinstance(control_indices, int) else list(control_indices)
 
         # Given TKET uses MSB convention, we will explicitly
         # convert the qubit indices to LSB convention
diff --git a/tests/circuit/test_ansatz.py b/tests/circuit/test_ansatz.py
index db960b9..c2d397e 100644
--- a/tests/circuit/test_ansatz.py
+++ b/tests/circuit/test_ansatz.py
@@ -18,7 +18,6 @@
 
 import pytest
 from quick.circuit import Ansatz, Circuit
-from typing import Type
 
 from tests.circuit import CIRCUIT_FRAMEWORKS
 
diff --git a/tests/circuit/test_circuit_base.py b/tests/circuit/test_circuit_base.py
index 298b2ba..c3634c8 100644
--- a/tests/circuit/test_circuit_base.py
+++ b/tests/circuit/test_circuit_base.py
@@ -19,7 +19,6 @@
 import numpy as np
 from numpy.testing import assert_almost_equal
 import pytest
-from typing import Type
 
 from quick.circuit import Circuit
 from quick.random import generate_random_state, generate_random_unitary
@@ -1313,7 +1312,7 @@ def test_eq(
     @pytest.mark.parametrize("circuit_framework", CIRCUIT_FRAMEWORKS)
     def test_eq_fail(
             self,
-            circuit_framework: Type[Circuit]
+            circuit_framework: type[Circuit]
         ) -> None:
         """ Test the `__eq__` dunder method failure.
 
@@ -1360,7 +1359,7 @@ def test_eq_fail(
     @pytest.mark.parametrize("circuit_framework", CIRCUIT_FRAMEWORKS)
     def test_eq_invalid_type(
             self,
-            circuit_framework: Type[Circuit]
+            circuit_framework: type[Circuit]
         ) -> None:
         """ Test the `__eq__` dunder method failure with invalid type.
 
@@ -1377,7 +1376,7 @@ def test_eq_invalid_type(
     @pytest.mark.parametrize("circuit_framework", CIRCUIT_FRAMEWORKS)
     def test_is_equivalent(
             self,
-            circuit_framework: Type[Circuit]
+            circuit_framework: type[Circuit]
         ) -> None:
         """ Test the `is_equivalent` method.
 
diff --git a/tests/circuit/test_circuit_decompose.py b/tests/circuit/test_circuit_decompose.py
index 9ac4a88..305208b 100644
--- a/tests/circuit/test_circuit_decompose.py
+++ b/tests/circuit/test_circuit_decompose.py
@@ -18,7 +18,6 @@
 
 import numpy as np
 import pytest
-from typing import Type
 
 from quick.circuit import Circuit
 
diff --git a/tests/circuit/test_circuit_to_controlled.py b/tests/circuit/test_circuit_to_controlled.py
index f2c9a96..b65553e 100644
--- a/tests/circuit/test_circuit_to_controlled.py
+++ b/tests/circuit/test_circuit_to_controlled.py
@@ -17,7 +17,6 @@
 __all__ = ["TestControlled"]
 
 import pytest
-from typing import Type
 
 from quick.circuit import Circuit
 
diff --git a/tests/circuit/test_control_state.py b/tests/circuit/test_control_state.py
index 2e121e3..3e2cbe2 100644
--- a/tests/circuit/test_control_state.py
+++ b/tests/circuit/test_control_state.py
@@ -18,7 +18,6 @@
 
 import numpy as np
 import pytest
-from typing import Type
 
 from quick.circuit import Circuit
 from quick.circuit.gate_matrix import RX
diff --git a/tests/circuit/test_qft_circuit.py b/tests/circuit/test_qft_circuit.py
index 5cff27b..4c4325c 100644
--- a/tests/circuit/test_qft_circuit.py
+++ b/tests/circuit/test_qft_circuit.py
@@ -20,7 +20,6 @@
 from numpy.testing import assert_almost_equal
 from numpy.typing import NDArray
 import pytest
-from typing import Type
 
 from quick.circuit import Circuit, CirqCircuit, PennylaneCircuit, QiskitCircuit, TKETCircuit
 
diff --git a/tests/synthesis/unitarypreparation/test_diffusion.py b/tests/synthesis/unitarypreparation/test_diffusion.py
index b1d698a..5f51f62 100644
--- a/tests/synthesis/unitarypreparation/test_diffusion.py
+++ b/tests/synthesis/unitarypreparation/test_diffusion.py
@@ -19,7 +19,6 @@
 from numpy.testing import assert_almost_equal
 import pytest
 import random
-from typing import Type
 
 from quick.circuit import Circuit, QiskitCircuit
 from quick.primitives import Operator