diff --git a/scaluq/gate/update_ops_dense_matrix.cpp b/scaluq/gate/update_ops_dense_matrix.cpp
index bc15364d..e0b02f87 100644
--- a/scaluq/gate/update_ops_dense_matrix.cpp
+++ b/scaluq/gate/update_ops_dense_matrix.cpp
@@ -20,6 +20,7 @@ void single_qubit_dense_matrix_gate(UINT target_qubit_index,
             state._raw[basis_0] = res0;
             state._raw[basis_1] = res1;
         });
+    Kokkos::fence();
 }
 
 void double_qubit_dense_matrix_gate(UINT target0,
@@ -49,6 +50,7 @@ void double_qubit_dense_matrix_gate(UINT target0,
             state._raw[basis_2] = res2;
             state._raw[basis_3] = res3;
         });
+    Kokkos::fence();
 }
 }  // namespace internal
 }  // namespace scaluq
diff --git a/scaluq/gate/update_ops_npair_qubit.cpp b/scaluq/gate/update_ops_npair_qubit.cpp
index 23dd8b81..1d72f0e1 100644
--- a/scaluq/gate/update_ops_npair_qubit.cpp
+++ b/scaluq/gate/update_ops_npair_qubit.cpp
@@ -31,6 +31,7 @@ void fusedswap_gate(UINT target_qubit_index_0,
                 Kokkos::Experimental::swap(state._raw[i], state._raw[j]);
             }
         });
+    Kokkos::fence();
 }
 }  // namespace internal
 }  // namespace scaluq
diff --git a/scaluq/gate/update_ops_one_control_one_target.cpp b/scaluq/gate/update_ops_one_control_one_target.cpp
index 505be5db..9d07f308 100644
--- a/scaluq/gate/update_ops_one_control_one_target.cpp
+++ b/scaluq/gate/update_ops_one_control_one_target.cpp
@@ -16,6 +16,7 @@ void cx_gate(UINT control_qubit_index, UINT target_qubit_index, StateVector& sta
             i |= 1ULL << control_qubit_index;
             Kokkos::Experimental::swap(state._raw[i], state._raw[i | (1ULL << target_qubit_index)]);
         });
+    Kokkos::fence();
 }
 
 void cz_gate(UINT control_qubit_index, UINT target_qubit_index, StateVector& state) {
@@ -27,6 +28,7 @@ void cz_gate(UINT control_qubit_index, UINT target_qubit_index, StateVector& sta
             i |= 1ULL << target_qubit_index;
             state._raw[i] *= -1;
         });
+    Kokkos::fence();
 }
 }  // namespace internal
 }  // namespace scaluq
diff --git a/scaluq/gate/update_ops_one_qubit.cpp b/scaluq/gate/update_ops_one_qubit.cpp
index 25a5a978..32bc365c 100644
--- a/scaluq/gate/update_ops_one_qubit.cpp
+++ b/scaluq/gate/update_ops_one_qubit.cpp
@@ -14,6 +14,7 @@ void x_gate(UINT target_qubit_index, StateVector& state) {
             UINT i = internal::insert_zero_to_basis_index(it, target_qubit_index);
             Kokkos::Experimental::swap(state._raw[i], state._raw[i | (1ULL << target_qubit_index)]);
         });
+    Kokkos::fence();
 }
 
 void y_gate(UINT target_qubit_index, StateVector& state) {
@@ -24,6 +25,7 @@ void y_gate(UINT target_qubit_index, StateVector& state) {
             state._raw[i | (1ULL << target_qubit_index)] *= Complex(0, -1);
             Kokkos::Experimental::swap(state._raw[i], state._raw[i | (1ULL << target_qubit_index)]);
         });
+    Kokkos::fence();
 }
 
 void z_gate(UINT target_qubit_index, StateVector& state) {
@@ -32,6 +34,7 @@ void z_gate(UINT target_qubit_index, StateVector& state) {
             UINT i = internal::insert_zero_to_basis_index(it, target_qubit_index);
             state._raw[i | (1ULL << target_qubit_index)] *= Complex(-1, 0);
         });
+    Kokkos::fence();
 }
 
 void h_gate(UINT target_qubit_index, StateVector& state) {
@@ -43,6 +46,7 @@ void h_gate(UINT target_qubit_index, StateVector& state) {
             state._raw[i] = (a + b) * INVERSE_SQRT2();
             state._raw[i | (1ULL << target_qubit_index)] = (a - b) * INVERSE_SQRT2();
         });
+    Kokkos::fence();
 }
 
 void single_qubit_phase_gate(UINT target_qubit_index, Complex phase, StateVector& state) {
@@ -51,6 +55,7 @@ void single_qubit_phase_gate(UINT target_qubit_index, Complex phase, StateVector
             UINT i = internal::insert_zero_to_basis_index(it, target_qubit_index);
             state._raw[i | (1ULL << target_qubit_index)] *= phase;
         });
+    Kokkos::fence();
 }
 
 void s_gate(UINT target_qubit_index, StateVector& state) {
@@ -113,6 +118,7 @@ void single_qubit_diagonal_matrix_gate(UINT target_qubit_index,
     Kokkos::parallel_for(
         state.dim(),
         KOKKOS_LAMBDA(UINT it) { state._raw[it] *= diag.val[(it >> target_qubit_index) & 1]; });
+    Kokkos::fence();
 }
 
 void rz_gate(UINT target_qubit_index, double angle, StateVector& state) {
diff --git a/scaluq/gate/update_ops_pauli.cpp b/scaluq/gate/update_ops_pauli.cpp
index 4331dbb2..21ef7b0b 100644
--- a/scaluq/gate/update_ops_pauli.cpp
+++ b/scaluq/gate/update_ops_pauli.cpp
@@ -31,6 +31,7 @@ void pauli_rotation_gate(const PauliOperator& pauli, double angle, StateVector&
                 }
                 state._raw[state_idx] *= coef;
             });
+        Kokkos::fence();
         return;
     } else {
         const UINT insert_idx = internal::BitVector(bit_flip_mask_vector).msb();
@@ -58,6 +59,7 @@ void pauli_rotation_gate(const PauliOperator& pauli, double angle, StateVector&
                 state._raw[basis_0] *= coef;
                 state._raw[basis_1] *= coef;
             });
+        Kokkos::fence();
     }
 }
 
diff --git a/scaluq/gate/update_ops_two_qubit.cpp b/scaluq/gate/update_ops_two_qubit.cpp
index bc142966..54dd2c68 100644
--- a/scaluq/gate/update_ops_two_qubit.cpp
+++ b/scaluq/gate/update_ops_two_qubit.cpp
@@ -15,6 +15,7 @@ void swap_gate(UINT target0, UINT target1, StateVector& state) {
             Kokkos::Experimental::swap(state._raw[basis | (1ULL << target0)],
                                        state._raw[basis | (1ULL << target1)]);
         });
+    Kokkos::fence();
 }
 }  // namespace internal
 }  // namespace scaluq
diff --git a/scaluq/gate/update_ops_zero_qubit.cpp b/scaluq/gate/update_ops_zero_qubit.cpp
index c2263210..fe13f51c 100644
--- a/scaluq/gate/update_ops_zero_qubit.cpp
+++ b/scaluq/gate/update_ops_zero_qubit.cpp
@@ -8,6 +8,7 @@ void global_phase_gate(double phase, StateVector& state) {
     Complex coef = Kokkos::polar(1., phase);
     Kokkos::parallel_for(
         state.dim(), KOKKOS_LAMBDA(UINT i) { state._raw[i] *= coef; });
+    Kokkos::fence();
 }
 }  // namespace internal
 }  // namespace scaluq
diff --git a/scaluq/operator/operator.cpp b/scaluq/operator/operator.cpp
index 0c66e323..fa5fc0cd 100644
--- a/scaluq/operator/operator.cpp
+++ b/scaluq/operator/operator.cpp
@@ -152,10 +152,10 @@ Complex Operator::get_expectation_value(const StateVector& state_vector) const {
                     res);
                 return coef * res;
             }();
-            team.team_barrier();
             Kokkos::single(Kokkos::PerTeam(team), [&] { term_res += tmp; });
         },
         res);
+    Kokkos::fence();
     return res;
 }
 
@@ -202,8 +202,8 @@ Complex Operator::get_transition_amplitude(const StateVector& state_vector_bra,
             UINT phase_flip_mask = pmasks[term_id];
             Complex coef = coefs[term_id];
             Complex tmp = [&] {
+                Complex res;
                 if (bit_flip_mask == 0) {
-                    Complex res;
                     Kokkos::parallel_reduce(
                         Kokkos::TeamThreadRange(team, dim),
                         [=](const UINT& state_idx, Complex& sum) {
@@ -213,32 +213,33 @@ Complex Operator::get_transition_amplitude(const StateVector& state_vector_bra,
                             sum += tmp;
                         },
                         res);
-                    return coef * res;
+                } else {
+                    UINT pivot = sizeof(UINT) * 8 - Kokkos::countl_zero(bit_flip_mask) - 1;
+                    UINT global_phase_90rot_count =
+                        Kokkos::popcount(bit_flip_mask & phase_flip_mask);
+                    Complex global_phase = PHASE_90ROT().val[global_phase_90rot_count % 4];
+                    Kokkos::parallel_reduce(
+                        Kokkos::TeamThreadRange(team, dim >> 1),
+                        [=](const UINT& state_idx, Complex& sum) {
+                            UINT basis_0 = internal::insert_zero_to_basis_index(state_idx, pivot);
+                            UINT basis_1 = basis_0 ^ bit_flip_mask;
+                            Complex tmp1 = Kokkos::conj(state_vector_bra._raw[basis_1]) *
+                                           state_vector_ket._raw[basis_0] * global_phase;
+                            if (Kokkos::popcount(basis_0 & phase_flip_mask) & 1) tmp1 = -tmp1;
+                            Complex tmp2 = Kokkos::conj(state_vector_bra._raw[basis_0]) *
+                                           state_vector_ket._raw[basis_1] * global_phase;
+                            if (Kokkos::popcount(basis_1 & phase_flip_mask) & 1) tmp2 = -tmp2;
+                            sum += tmp1 + tmp2;
+                        },
+                        res);
                 }
-                UINT pivot = sizeof(UINT) * 8 - Kokkos::countl_zero(bit_flip_mask) - 1;
-                UINT global_phase_90rot_count = Kokkos::popcount(bit_flip_mask & phase_flip_mask);
-                Complex global_phase = PHASE_90ROT().val[global_phase_90rot_count % 4];
-                Complex res;
-                Kokkos::parallel_reduce(
-                    Kokkos::TeamThreadRange(team, dim >> 1),
-                    [=](const UINT& state_idx, Complex& sum) {
-                        UINT basis_0 = internal::insert_zero_to_basis_index(state_idx, pivot);
-                        UINT basis_1 = basis_0 ^ bit_flip_mask;
-                        Complex tmp1 = Kokkos::conj(state_vector_bra._raw[basis_1]) *
-                                       state_vector_ket._raw[basis_0] * global_phase;
-                        if (Kokkos::popcount(basis_0 & phase_flip_mask) & 1) tmp1 = -tmp1;
-                        Complex tmp2 = Kokkos::conj(state_vector_bra._raw[basis_0]) *
-                                       state_vector_ket._raw[basis_1] * global_phase;
-                        if (Kokkos::popcount(basis_1 & phase_flip_mask) & 1) tmp2 = -tmp2;
-                        sum += tmp1 + tmp2;
-                    },
-                    res);
+                team.team_barrier();
                 return coef * res;
             }();
-            team.team_barrier();
             Kokkos::single(Kokkos::PerTeam(team), [&] { term_res += tmp; });
         },
         res);
+    Kokkos::fence();
     return res;
 }
 
diff --git a/scaluq/operator/pauli_operator.cpp b/scaluq/operator/pauli_operator.cpp
index 4397a2ff..a7cc0faa 100644
--- a/scaluq/operator/pauli_operator.cpp
+++ b/scaluq/operator/pauli_operator.cpp
@@ -125,6 +125,7 @@ void PauliOperator::apply_to_state(StateVector& state_vector) const {
                     state_vector._raw[state_idx] *= coef;
                 }
             });
+        Kokkos::fence();
         return;
     }
     UINT pivot = sizeof(UINT) * 8 - std::countl_zero(bit_flip_mask) - 1;
@@ -141,6 +142,7 @@ void PauliOperator::apply_to_state(StateVector& state_vector) const {
             state_vector._raw[basis_0] = tmp2 * coef;
             state_vector._raw[basis_1] = tmp1 * coef;
         });
+    Kokkos::fence();
 }
 
 Complex PauliOperator::get_expectation_value(const StateVector& state_vector) const {
@@ -206,6 +208,7 @@ Complex PauliOperator::get_transition_amplitude(const StateVector& state_vector_
                 sum += tmp;
             },
             res);
+        Kokkos::fence();
         return _coef * res;
     }
     UINT pivot = sizeof(UINT) * 8 - std::countl_zero(bit_flip_mask) - 1;
@@ -226,6 +229,7 @@ Complex PauliOperator::get_transition_amplitude(const StateVector& state_vector_
             sum += tmp1 + tmp2;
         },
         res);
+    Kokkos::fence();
     return _coef * res;
 }
 
diff --git a/scaluq/state/state_vector.cpp b/scaluq/state/state_vector.cpp
index 4caea3ed..db44672a 100644
--- a/scaluq/state/state_vector.cpp
+++ b/scaluq/state/state_vector.cpp
@@ -51,6 +51,7 @@ StateVector StateVector::Haar_random_state(UINT n_qubits, UINT seed) {
             state._raw[i] = Complex(rand_gen.normal(0.0, 1.0), rand_gen.normal(0.0, 1.0));
             rand_pool.free_state(rand_gen);
         });
+    Kokkos::fence();
     state.normalize();
     return state;
 }
@@ -76,6 +77,7 @@ void StateVector::normalize() {
     const auto norm = std::sqrt(this->get_squared_norm());
     Kokkos::parallel_for(
         this->_dim, KOKKOS_CLASS_LAMBDA(UINT it) { this->_raw[it] /= norm; });
+    Kokkos::fence();
 }
 
 double StateVector::get_zero_probability(UINT target_qubit_index) const {
@@ -159,16 +161,19 @@ double StateVector::get_entropy() const {
 void StateVector::add_state_vector(const StateVector& state) {
     Kokkos::parallel_for(
         this->_dim, KOKKOS_CLASS_LAMBDA(UINT i) { this->_raw[i] += state._raw[i]; });
+    Kokkos::fence();
 }
 
 void StateVector::add_state_vector_with_coef(const Complex& coef, const StateVector& state) {
     Kokkos::parallel_for(
         this->_dim, KOKKOS_CLASS_LAMBDA(UINT i) { this->_raw[i] += coef * state._raw[i]; });
+    Kokkos::fence();
 }
 
 void StateVector::multiply_coef(const Complex& coef) {
     Kokkos::parallel_for(
         this->_dim, KOKKOS_CLASS_LAMBDA(UINT i) { this->_raw[i] *= coef; });
+    Kokkos::fence();
 }
 
 std::vector<UINT> StateVector::sampling(UINT sampling_count, UINT seed) const {
@@ -201,6 +206,7 @@ std::vector<UINT> StateVector::sampling(UINT sampling_count, UINT seed) const {
             result[i] = lo;
             rand_pool.free_state(rand_gen);
         });
+    Kokkos::fence();
     return internal::convert_device_view_to_host_vector(result);
 }