Error_M

 Still thinking quantum...

Thought I would start looking through various error mitigation techniques, what they are,

what they do. One can enable them within qiskit, run on a simulator but, to be real, run them

on an actual quantum computer. They are run on the Estimator primitives (as opposed to

the Sampler).

Errors can sometimes show up on idling qubits ie qubits not being called up while performing

a given operation.

Dynamical decoupling works by inserting pulse sequences on idling qubits to approximately cancel out the effect of these errors. Each inserted pulse sequence amounts to an identity operation, but the physical presence of the pulses has the effect of suppressing errors.

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First, need to learn about using Estimator:

Primitives examples | IBM Quantum Documentation

This code snippet demonstrates how to:

1. Initialize the Qiskit Runtime Service and select a backend.

2. Create a quantum circuit using the IQP (Instantaneous Quantum Polynomial) circuit.

3. Define an observable using the SparsePauliOp class.

4. Transpile the circuit to match the backend's instruction set architecture.

5. Initialize the Estimator primitive.

6. Run the Estimator to calculate the expectation value of the circuit with the given observable.

7. Print the expectation value and metadata.

                                                             

Measurement Basis:

                                                                              

Expectation Value: