Quantum Phase Estimation - Continue with Multiple Qubits

In my previous article, I wrote an introduction to quantum phase estimation and explained the working principle of a quantum circuit for a single qubit.

As I mentioned before, in order to obtain the quantum phase precisely, we will either repeat our algorithm continuously or find a precise quantum phase in one goes using multiple qubits. The most logical solution is to create our quantum circuit with many qubits.

So let's look at the details of our quantum circuit!

This may remind you of the quantum Fourier transform. Yes, it's definitely a good guess. In the last step, if we apply the inverse quantum Fourier transform and measure, we will

probably get the 2nϕ phase.

Using multiple qubits, we found our quantum phase. We can now apply it to its important application, Shor's algorithm.

Stay curious. :)

Reference

https://www.youtube.com/watch?v=PhhsGb-pY94&list=PLqNc_xpYGu775P7iJA7Kvfxmv_Fm9wwHj&index=14

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