
Learn Quantum Computing with Python and IBM Quantum
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As described in Chapter 5, Understanding the Qubit, two or more qubits can combine their states by their tensor product, sometimes referred to as the Kronecker product.
In this section, we will discuss the multi-qubit gates and how they operate on the qubits similarly to how single-qubit gates do, which includes them being unitary and reversible.
To keep the descriptions and examples uniform, the following descriptions of the multi-qubit gates will be presented the same way as the single-qubit gates. We will open the helper file again and review another function titled execute_circuit_returns
. The helper function will have a few differences, the first of which will be the Qiskit primitive Sampler to run our circuits. We are using this for now so that you don’t use up your quantum hardware allotted time on these simple circuits. Save the hardware for the fun work later in this book. Also, just like the previous helper function we used...