Summary
In this chapter, we have studied how to work with two-qubit circuits in Qiskit. We described how to define this type of circuit and how to apply gates to individual qubits. We also discussed how to apply two-qubit operations such as the CNOT gate, and we learned how to retrieve results from our circuits by performing measurements in a number of ways.
We illustrated all of these concepts with three important examples: superdense coding, the CHSH game, and Deutsch’s algorithm. We had the opportunity to check the inner workings of these algorithms and protocols on both simulators and actual quantum computers, and we also explored some handy tricks such as sending a bunch of different circuits in the same job.
In the following chapter, we will begin to unlock the full potential of quantum computing by introducing systems with an arbitrary number of qubits. This will allow us to later discuss even more impressive quantum algorithms (such as a generalization of Deutsch’...
