From fd9c5755fb825a22aad807974fd974ad5ad18c1d Mon Sep 17 00:00:00 2001
From: Toshinari Itoko <itoko@jp.ibm.com>
Date: Thu, 9 Nov 2023 12:32:33 +0900
Subject: [PATCH] Fix for supporting BackendV2 simulators

---
 .../randomized_benchmarking/standard_rb.py    | 37 +++++++++++--------
 1 file changed, 21 insertions(+), 16 deletions(-)

diff --git a/qiskit_experiments/library/randomized_benchmarking/standard_rb.py b/qiskit_experiments/library/randomized_benchmarking/standard_rb.py
index 61c3bb03a7..fe3344200d 100644
--- a/qiskit_experiments/library/randomized_benchmarking/standard_rb.py
+++ b/qiskit_experiments/library/randomized_benchmarking/standard_rb.py
@@ -233,21 +233,26 @@ def _get_synthesis_options(self) -> Dict[str, Optional[Any]]:
             coupling_map = coupling_map.reduce(self.physical_qubits)
         if not (basis_gates and coupling_map) and self.backend:
             if isinstance(self.backend, BackendV2) and self.backend.target:
-                backend_basis_gates = []
-                backend_cmap = None
-                for op in self.backend.target.operations:
-                    if op.num_qubits == 2:
-                        cmap = self.backend.target.build_coupling_map(op.name)
-                        if cmap:
-                            reduced = cmap.reduce(self.physical_qubits)
-                            if rx.is_weakly_connected(reduced.graph):
+                if "simulator" in self.backend.name:
+                    basis_gates = basis_gates if basis_gates else self.backend.target.operation_names
+                    coupling_map = coupling_map if coupling_map else None
+                else:
+                    backend_basis_gates = [op.name for op in self.backend.target.operations if op.num_qubits != 2]
+                    backend_cmap = None
+                    for op in self.backend.target.operations:
+                        if op.num_qubits == 2:
+                            cmap = self.backend.target.build_coupling_map(op.name)
+                            if cmap is None:
                                 backend_basis_gates.append(op.name)
-                                backend_cmap = reduced
-                                break
-                    else:
-                        backend_basis_gates.append(op.name)
-                basis_gates = basis_gates if basis_gates else backend_basis_gates
-                coupling_map = coupling_map if coupling_map else backend_cmap
+                            else:
+                                reduced = cmap.reduce(self.physical_qubits)
+                                if rx.is_weakly_connected(reduced.graph):
+                                    backend_basis_gates.append(op.name)
+                                    backend_cmap = reduced
+                                    # take the first non-global 2q gate if the backend supports multiple 2q gates
+                                    break
+                    basis_gates = basis_gates if basis_gates else backend_basis_gates
+                    coupling_map = coupling_map if coupling_map else backend_cmap
             elif isinstance(self.backend, BackendV1):
                 backend_basis_gates = self.backend.configuration().basis_gates
                 backend_cmap = self.backend.configuration().coupling_map
@@ -377,8 +382,8 @@ def _transpiled_circuits(self) -> List[QuantumCircuit]:
                 _transpile_clifford_circuit(circ, physical_qubits=self.physical_qubits)
                 for circ in self.circuits()
             ]
-            # Set custom calibrations provided in backend
-            if isinstance(self.backend, BackendV2):
+            # Set custom calibrations provided in backend (excluding simulators)
+            if isinstance(self.backend, BackendV2) and "simulator" not in self.backend.name:
                 qargs_patterns = [self.physical_qubits]  # for 1q or 3q+ case
                 if self.num_qubits == 2:
                     qargs_patterns = [