Add mitigated tomo tests

test/library/tomography/test_process_tomography.py

@@ -22,10 +22,16 @@
 import qiskit.quantum_info as qi
 from qiskit_aer import AerSimulator
 from qiskit_aer.noise import NoiseModel
-from qiskit_experiments.library import ProcessTomography
-from qiskit_experiments.library.tomography import ProcessTomographyAnalysis, basis
 from qiskit_experiments.database_service import ExperimentEntryNotFound
-from .tomo_utils import FITTERS, filter_results, teleport_circuit, teleport_bell_circuit
+from qiskit_experiments.library import ProcessTomography, MitigatedProcessTomography
+from qiskit_experiments.library.tomography import ProcessTomographyAnalysis, basis
+from .tomo_utils import (
+    FITTERS,
+    filter_results,
+    teleport_circuit,
+    teleport_bell_circuit,
+    readout_noise_model,
+)
 
 
 @ddt.ddt
@@ -441,3 +447,52 @@ def test_qpt_amat_pauli_basis(self):
         self.assertExperimentDone(expdata)
         fid = expdata.analysis_results("process_fidelity").value
         self.assertGreater(fid, 0.95)
+
+    @ddt.data((0,), (1,), (2,), (3,), (0, 1), (2, 0), (0, 3))
+    def test_mitigated_full_qpt_random_unitary(self, qubits):
+        """Test QPT experiment"""
+        seed = 1234
+        shots = 5000
+        f_threshold = 0.95
+
+        noise_model = readout_noise_model(4, seed=seed)
+        backend = AerSimulator(seed_simulator=seed, shots=shots, noise_model=noise_model)
+        target = qi.random_unitary(2 ** len(qubits), seed=seed)
+        exp = MitigatedProcessTomography(target, backend=backend)
+        exp.analysis.set_options(unmitigated_fit=True)
+        expdata = exp.run(analysis=None)
+        self.assertExperimentDone(expdata)
+
+        for fitter in FITTERS:
+            with self.subTest(fitter=fitter, qubits=qubits):
+                if fitter:
+                    exp.analysis.set_options(fitter=fitter)
+                fitdata = exp.analysis.run(expdata)
+                self.assertExperimentDone(fitdata)
+                # Should be 2 results, mitigated and unmitigated
+                states = expdata.analysis_results("state")
+                self.assertEqual(len(states), 2)
+
+                # Check state is density matrix
+                for state in states:
+                    self.assertTrue(
+                        isinstance(state.value, qi.Choi),
+                        msg=f"{fitter} fitted state is not density matrix for qubits {qubits}",
+                    )
+
+                # Check fit state fidelity
+                fids = expdata.analysis_results("process_fidelity")
+                self.assertEqual(len(fids), 2)
+                mitfid, nomitfid = fids
+                # Check mitigation improves fidelity
+                self.assertTrue(
+                    mitfid.value >= nomitfid.value,
+                    msg="mitigated {} did not improve fidelity for qubits {} ({:.4f} < {:.4f})".format(
+                        fitter, qubits, mitfid.value, nomitfid.value
+                    ),
+                )
+                self.assertGreater(
+                    mitfid.value,
+                    f_threshold,
+                    msg=f"{fitter} fit fidelity is low for qubits {qubits}",
+                )

test/library/tomography/test_state_tomography.py

@@ -24,10 +24,16 @@
 from qiskit_aer import AerSimulator
 from qiskit_aer.noise import NoiseModel
 
-from qiskit_experiments.library import StateTomography
-from qiskit_experiments.library.tomography import StateTomographyAnalysis, basis
 from qiskit_experiments.database_service import ExperimentEntryNotFound
-from .tomo_utils import FITTERS, filter_results, teleport_circuit, teleport_bell_circuit
+from qiskit_experiments.library import StateTomography, MitigatedStateTomography
+from qiskit_experiments.library.tomography import StateTomographyAnalysis, basis
+from .tomo_utils import (
+    FITTERS,
+    filter_results,
+    teleport_circuit,
+    teleport_bell_circuit,
+    readout_noise_model,
+)
 
 
 @ddt.ddt
@@ -341,3 +347,50 @@ def test_qst_amat_pauli_basis(self):
         self.assertExperimentDone(expdata)
         fid = expdata.analysis_results("state_fidelity").value
         self.assertGreater(fid, 0.95)
+
+    @ddt.data((0,), (1,), (2,), (3,), (0, 1), (2, 0), (0, 3), (0, 3, 1))
+    def test_mitigated_full_qst(self, qubits):
+        """Test QST experiment"""
+        seed = 1234
+        shots = 5000
+        f_threshold = 0.95
+
+        noise_model = readout_noise_model(4, seed=seed)
+        backend = AerSimulator(seed_simulator=seed, shots=shots, noise_model=noise_model)
+        target = qi.random_statevector(2 ** len(qubits), seed=seed)
+        exp = MitigatedStateTomography(target, physical_qubits=qubits, backend=backend)
+        exp.analysis.set_options(unmitigated_fit=True)
+        expdata = exp.run(analysis=None)
+        self.assertExperimentDone(expdata)
+
+        for fitter in FITTERS:
+            with self.subTest(fitter=fitter, qubits=qubits):
+                if fitter:
+                    exp.analysis.set_options(fitter=fitter)
+                fitdata = exp.analysis.run(expdata)
+                self.assertExperimentDone(fitdata)
+                # Should be 2 results, mitigated and unmitigated
+                states = expdata.analysis_results("state")
+                self.assertEqual(len(states), 2)
+                for state in states:
+                    self.assertTrue(
+                        isinstance(state.value, qi.DensityMatrix),
+                        msg=f"{fitter} fitted state is not density matrix for qubits {qubits}",
+                    )
+
+                # Check fit state fidelity
+                fids = expdata.analysis_results("state_fidelity")
+                self.assertEqual(len(fids), 2)
+                mitfid, nomitfid = fids
+                # Check mitigation improves fidelity
+                self.assertTrue(
+                    mitfid.value >= nomitfid.value,
+                    msg="mitigated {} did not improve fidelity for qubits {} ({:.4f} < {:.4f})".format(
+                        fitter, qubits, mitfid.value, nomitfid.value
+                    ),
+                )
+                self.assertGreater(
+                    mitfid.value,
+                    f_threshold,
+                    msg=f"{fitter} fit fidelity is low for qubits {qubits}",
+                )

test/library/tomography/tomo_utils.py

@@ -13,7 +13,9 @@
 """
 Common methods for tomography tests
 """
+import numpy as np
 from qiskit import QuantumCircuit, ClassicalRegister, QuantumRegister
+from qiskit_aer.noise import NoiseModel
 
 
 FITTERS = [
@@ -77,3 +79,15 @@ def teleport_bell_circuit(flatten_creg=True):
     teleport.z(2).c_if(creg[0], 1)
     teleport.x(2).c_if(creg[1], 1)
     return teleport
+
+
+def readout_noise_model(num_qubits, seed=None):
+    """Generate noise model of random local readout errors"""
+    rng = np.random.default_rng(seed=seed)
+    p1g0s = 0.15 * rng.random(num_qubits)
+    p0g1s = 0.3 * rng.random(num_qubits)
+    amats = np.stack([[1 - p1g0s, p1g0s], [p0g1s, 1 - p0g1s]]).T
+    noise_model = NoiseModel()
+    for i, amat in enumerate(amats):
+        noise_model.add_readout_error(amat.T, [i])
+    return noise_model