diff --git a/tests/test_backends.py b/tests/test_backends.py
index 9155efec8c..a4714bd378 100644
--- a/tests/test_backends.py
+++ b/tests/test_backends.py
@@ -3,7 +3,7 @@
 
 from qibo import gates
 
-####################### Test `asmatrix` #######################
+####################### Test `matrix` #######################
 GATES = [
     ("H", (0,), np.array([[1, 1], [1, -1]]) / np.sqrt(2)),
     ("X", (0,), np.array([[0, 1], [1, 0]])),
@@ -47,9 +47,9 @@
 
 
 @pytest.mark.parametrize("gate,qubits,target_matrix", GATES)
-def test_asmatrix(backend, gate, qubits, target_matrix):
+def test_matrix(backend, gate, qubits, target_matrix):
     gate = getattr(gates, gate)(*qubits)
-    backend.assert_allclose(gate.asmatrix(backend), target_matrix)
+    backend.assert_allclose(gate.matrix(backend), target_matrix)
 
 
 GATES = [
@@ -75,15 +75,15 @@ def test_asmatrix(backend, gate, qubits, target_matrix):
 
 
 @pytest.mark.parametrize("gate,target_matrix", GATES)
-def test_asmatrix_rotations(backend, gate, target_matrix):
+def test_matrix_rotations(backend, gate, target_matrix):
     """Check that `_construct_unitary` method constructs the proper matrix."""
     theta = 0.1234
     if gate == "CU1":
         gate = getattr(gates, gate)(0, 1, theta)
     else:
         gate = getattr(gates, gate)(0, theta)
-    backend.assert_allclose(gate.asmatrix(backend), target_matrix(theta))
-    backend.assert_allclose(gate.asmatrix(backend), target_matrix(theta))
+    backend.assert_allclose(gate.matrix(backend), target_matrix(theta))
+    backend.assert_allclose(gate.matrix(backend), target_matrix(theta))
 
 
 def test_control_matrix(backend):
@@ -97,7 +97,7 @@ def test_control_matrix(backend):
     target_matrix = np.eye(4, dtype=rotation.dtype)
     target_matrix[2:, 2:] = rotation
     gate = gates.RY(0, theta).controlled_by(1)
-    backend.assert_allclose(gate.asmatrix(backend), target_matrix)
+    backend.assert_allclose(gate.matrix(backend), target_matrix)
 
     gate = gates.RY(0, theta).controlled_by(1, 2)
     with pytest.raises(NotImplementedError):
diff --git a/tests/test_gates_abstract.py b/tests/test_gates_abstract.py
index 7711bb61a8..133f103ca0 100644
--- a/tests/test_gates_abstract.py
+++ b/tests/test_gates_abstract.py
@@ -222,7 +222,7 @@ def test_pauli_noise_channel_init(backend):
     assert gate.target_qubits == (0,)
     for g, p in zip(gate.gates, [matrices.X, matrices.Y, matrices.Z]):
         p = backend.cast(p, dtype=p.dtype)
-        backend.assert_allclose(g.asmatrix(backend), p, atol=PRECISION_TOL)
+        backend.assert_allclose(g.matrix(backend), p, atol=PRECISION_TOL)
 
 
 def test_reset_channel_init():
diff --git a/tests/test_gates_density_matrix.py b/tests/test_gates_density_matrix.py
index 8c53048ffa..19d6c66bf8 100644
--- a/tests/test_gates_density_matrix.py
+++ b/tests/test_gates_density_matrix.py
@@ -70,7 +70,7 @@ def test_one_qubit_gates(backend, gatename, gatekwargs):
     gate = getattr(gates, gatename)(0, **gatekwargs)
     final_rho = apply_gates(backend, [gate], 1, initial_rho)
 
-    matrix = backend.to_numpy(gate.asmatrix(backend))
+    matrix = backend.to_numpy(gate.matrix(backend))
     target_rho = np.einsum("ab,bc,cd->ad", matrix, initial_rho, matrix.conj().T)
     backend.assert_allclose(final_rho, target_rho)
 
@@ -82,7 +82,7 @@ def test_controlled_by_one_qubit_gates(backend, gatename):
     gate = getattr(gates, gatename)(1).controlled_by(0)
     final_rho = apply_gates(backend, [gate], 2, initial_rho)
 
-    matrix = backend.to_numpy(backend.asmatrix(getattr(gates, gatename)(1)))
+    matrix = backend.to_numpy(backend.matrix(getattr(gates, gatename)(1)))
     cmatrix = np.eye(4, dtype=matrix.dtype)
     cmatrix[2:, 2:] = matrix
     target_rho = np.einsum("ab,bc,cd->ad", cmatrix, initial_rho, cmatrix.conj().T)
@@ -111,7 +111,7 @@ def test_two_qubit_gates(backend, gatename, gatekwargs):
     gate = getattr(gates, gatename)(0, 1, **gatekwargs)
     final_rho = apply_gates(backend, [gate], 2, initial_rho)
 
-    matrix = backend.to_numpy(gate.asmatrix(backend))
+    matrix = backend.to_numpy(gate.matrix(backend))
     target_rho = np.einsum("ab,bc,cd->ad", matrix, initial_rho, matrix.conj().T)
     backend.assert_allclose(final_rho, target_rho, atol=PRECISION_TOL)
 
@@ -123,7 +123,7 @@ def test_toffoli_gate(backend):
     gate = gates.TOFFOLI(0, 1, 2)
     final_rho = apply_gates(backend, [gate], 3, initial_rho)
 
-    matrix = backend.to_numpy(gate.asmatrix(backend))
+    matrix = backend.to_numpy(gate.matrix(backend))
     target_rho = np.einsum("ab,bc,cd->ad", matrix, initial_rho, matrix.conj().T)
     backend.assert_allclose(final_rho, target_rho)
 
diff --git a/tests/test_gates_gates.py b/tests/test_gates_gates.py
index 5826975276..3bb906c60d 100644
--- a/tests/test_gates_gates.py
+++ b/tests/test_gates_gates.py
@@ -214,7 +214,7 @@ def test_align(backend):
 
     backend.assert_allclose(final_state, target_state)
 
-    gate_matrix = gate.asmatrix(backend)
+    gate_matrix = gate.matrix(backend)
     identity = backend.identity_density_matrix(nqubits, normalize=False)
     backend.assert_allclose(gate_matrix, identity)
 
@@ -559,7 +559,8 @@ def test_cun(backend, name, params):
 
     final_state = apply_gates(backend, [gate], initial_state=initial_state)
 
-    gate = backend.cast(gate.matrix, dtype=gate.matrix.dtype)
+    _matrix = gate.matrix(backend)
+    gate = backend.cast(_matrix, dtype=_matrix.dtype)
 
     target_state = np.dot(gate, initial_state)
 
@@ -1472,7 +1473,7 @@ def test_gate_basis_rotation(backend):
     gate = gates.Y(0).basis_rotation()
     assert isinstance(gate, gates.Unitary)
     target_matrix = np.array([[1, -1j], [1j, -1]]) / np.sqrt(2)
-    backend.assert_allclose(gate.asmatrix(backend), target_matrix)
+    backend.assert_allclose(gate.matrix(backend), target_matrix)
     with pytest.raises(NotImplementedError):
         gates.RX(0, np.pi / 2).basis_rotation()
 
diff --git a/tests/test_gates_special.py b/tests/test_gates_special.py
index 53ec1846c2..472d4e371f 100644
--- a/tests/test_gates_special.py
+++ b/tests/test_gates_special.py
@@ -12,7 +12,7 @@ def test_callback_gate_errors(backend):
     with pytest.raises(NotImplementedError):
         gate.on_qubits(2)
     with pytest.raises(NotImplementedError):
-        gate.asmatrix(backend)
+        gate.matrix(backend)
 
 
 @pytest.mark.parametrize("nqubits", [2, 3])
@@ -29,4 +29,4 @@ def test_fused_gate_construct_unitary(backend, nqubits):
         toffoli = np.eye(8)
         toffoli[-2:, -2:] = np.array([[0, 1], [1, 0]])
         target_matrix = toffoli @ np.kron(target_matrix, np.eye(2))
-    backend.assert_allclose(gate.asmatrix(backend), target_matrix)
+    backend.assert_allclose(gate.matrix(backend), target_matrix)
diff --git a/tests/test_hamiltonians.py b/tests/test_hamiltonians.py
index 5c3c04c3d8..960dbc797d 100644
--- a/tests/test_hamiltonians.py
+++ b/tests/test_hamiltonians.py
@@ -193,7 +193,7 @@ def test_hamiltonian_matmul_states(backend, sparse_type):
     m = random_complex((2**nqubits, 2**nqubits), dtype=hm.dtype)
     Hv = H @ backend.cast(v)
     Hm = H @ backend.cast(m)
-    backend.assert_allclose(Hv, hm.dot(v))
+    backend.assert_allclose(Hv, hm.dot(v), atol=1e-7)  # needs atol for cuquantum
     backend.assert_allclose(Hm, (hm @ m))
 
     Hstate = H @ backend.cast(v)
diff --git a/tests/test_hamiltonians_from_symbols.py b/tests/test_hamiltonians_from_symbols.py
index 34c0c596ae..4208ab5fb7 100644
--- a/tests/test_hamiltonians_from_symbols.py
+++ b/tests/test_hamiltonians_from_symbols.py
@@ -4,6 +4,7 @@
 import sympy
 
 from qibo import hamiltonians, matrices
+from qibo.backends import NumpyBackend
 from qibo.quantum_info import random_hermitian
 from qibo.symbols import I, Symbol, X, Y, Z
 
@@ -42,8 +43,9 @@ def test_tfim_hamiltonian_from_symbols(backend, nqubits, hamtype, calcterms):
 @pytest.mark.parametrize("calcterms", [False, True])
 def test_from_symbolic_with_power(backend, hamtype, calcterms):
     """Check ``from_symbolic`` when the expression contains powers."""
+    npbackend = NumpyBackend()
     if hamtype == "symbolic":
-        matrix = random_hermitian(2)
+        matrix = random_hermitian(2, backend=npbackend)
         symham = (
             Symbol(0, matrix) ** 2
             - Symbol(1, matrix) ** 2
@@ -55,12 +57,13 @@ def test_from_symbolic_with_power(backend, hamtype, calcterms):
     else:
         z = sympy.symbols(" ".join(f"Z{i}" for i in range(3)))
         symham = z[0] ** 2 - z[1] ** 2 + 3 * z[1] - 2 * z[0] * z[2] + 1
-        matrix = random_hermitian(2)
+        matrix = random_hermitian(2, backend=npbackend)
         symmap = {x: (i, matrix) for i, x in enumerate(z)}
         ham = hamiltonians.Hamiltonian.from_symbolic(symham, symmap, backend=backend)
 
     if calcterms:
         _ = ham.terms
+
     final_matrix = ham.matrix
     matrix2 = matrix.dot(matrix)
     eye = np.eye(2, dtype=matrix.dtype)
diff --git a/tests/test_hamiltonians_terms.py b/tests/test_hamiltonians_terms.py
index c13b8dc995..f0a0703757 100644
--- a/tests/test_hamiltonians_terms.py
+++ b/tests/test_hamiltonians_terms.py
@@ -44,7 +44,7 @@ def test_hamiltonian_term_gates(backend):
     term = terms.HamiltonianTerm(matrix, 1, 2)
     gate = term.gate
     assert gate.target_qubits == (1, 2)
-    backend.assert_allclose(gate.asmatrix(backend), matrix)
+    backend.assert_allclose(gate.matrix(backend), matrix)
 
     initial_state = random_statevector(2**nqubits, backend=backend)
     final_state = term(backend, np.copy(initial_state), nqubits)
diff --git a/tests/test_measurements.py b/tests/test_measurements.py
index 276b6e67b1..3b0bcea4d5 100644
--- a/tests/test_measurements.py
+++ b/tests/test_measurements.py
@@ -96,7 +96,7 @@ def test_measurement_gate_errors(backend):
         gate.controlled_by(1)
     # attempting to construct unitary
     with pytest.raises(NotImplementedError):
-        matrix = gate.matrix
+        matrix = gate.matrix(backend)
 
 
 def test_measurement_circuit(backend, accelerators):
diff --git a/tests/test_models_circuit_fuse.py b/tests/test_models_circuit_fuse.py
index 8ff7c20f4c..4e7c323f2e 100644
--- a/tests/test_models_circuit_fuse.py
+++ b/tests/test_models_circuit_fuse.py
@@ -18,7 +18,7 @@ def test_fused_gate_construct_unitary(backend, nqubits):
         toffoli = np.eye(8)
         toffoli[-2:, -2:] = np.array([[0, 1], [1, 0]])
         target_matrix = toffoli @ np.kron(target_matrix, np.eye(2))
-    backend.assert_allclose(gate.asmatrix(backend), target_matrix)
+    backend.assert_allclose(gate.matrix(backend), target_matrix)
 
 
 def test_single_fusion_gate():
@@ -66,7 +66,7 @@ def test_fusedgate_matrix_calculation(backend):
     h = np.array([[1, 1], [1, -1]]) / np.sqrt(2)
     cnot = np.array([[1, 0, 0, 0], [0, 1, 0, 0], [0, 0, 0, 1], [0, 0, 1, 0]])
     target_matrix = np.kron(x, x) @ cnot @ np.kron(h, h)
-    fused_matrix = fused_gate.asmatrix(backend)
+    fused_matrix = fused_gate.matrix(backend)
     backend.assert_allclose(fused_matrix, target_matrix)