According to this answer by rrtucci , I still cannot catch the spirit of QFT algorithm. So I would like to ask why we are using Hadamard Gate when computing Fourier Transform? Moreover, what is the main idea behind Hadamard Gate? Thank you!

For my summer research internship I'm looking to randomized benchmark (RB) non-Clifford gates for a single qubit. Since I found out that Qiskit ignis allows for the RB of Clifford gates (https://github.com/Qiskit/qiskit-tutorials/blob/master/qiskit/ignis/randomized_benchmarking.ipynb), naturally ...

I was reading a paper on Quantum Neural Networks where the authors discussed a new back propagation algorithm. They shared a schematic of the circuit. However, I am unable to understand how the proposed circuit can be derived from the equations derived. Can anybody shed some light? The paper can...

Let the Werner state $$\rho_W = W\mid\Psi^-\rangle\langle\Psi^-\mid + \frac{1-W}{4}\mathbb{I},\ W\in [0,1],$$ where $|\Psi^-\rangle=(|01\rangle+|10\rangle)/\sqrt{2}$. I have repeatedly heard that such a state is separable if $W\leq\frac{1}{3}$ and entangled otherwise. I would like to see where e...

I am trying to implement Simon's algorithm which calls for a 2-to-1 mapping function that satisfies f(x) = f(x⊕s). I am looking for a simple way to code the oracle (using H, Cx, and R gates), ideally with an easy way to redefine s.

I read the article of IBM on Quantum Volume. But I don't understand how to calculate effective error rate, and therefore the Quantum Volume. If someone have an example of calculation ?

I am attempting to implement a minimum spanning tree problem on the D wave quantum computing architecture. I have seen many graph problems implemented, such as a graph coloring example. There are also a variety of Traveling Salesman Tutorials available. What would be the best approach for making ...