Is it possible to design a circuit implementing the unitary matrix
$$U-\begin{bmatrix} R_{\Theta_1} & 0 & 0 & 0 \\ 0 & R_{\Theta_2} & 0 & 0 \\ 0 & 0 & R_{\Theta_3} & 0 \\ 0 & 0 & 0 & R_{\Theta_4} \\ \end{bmatrix}$$
for given four angles $\Theta_1,...,\Theta_4$ , where 0 is 2×2-dimensional zero matrix and $R_{\Theta}$ is the rotation matrix with angle $\Theta$?
If so, can we implement it on the available quantum programming platforms such as Qiskit, CirQ, PyQuil, or ProjectQ?
qiskit
, you can firstfrom qiskit.quantum_info.operators import Operator
, and thenO=Operator(yourUnitaryMatrix)
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