In Qiskit, how do I construct a circuit corresponding to the Trotter expansion of a Pauli sum $A+B+C+\ldots$ given as a WightedPauliSum
object?
$$
\operatorname{e}^{A + B + C + \ldots } \overset{?}{\mapsto}
\left\{\begin{alignedat}{9}
U &= \operatorname{e}^{A}\operatorname{e}^{B}\operatorname{e}^{C}\ldots \ &&, \quad &&\text{(first order)}\\
U &= \operatorname{e}^{A/2}\operatorname{e}^{B/2}\operatorname{e}^{C/2}\ldots\operatorname{e}^{C/2}\operatorname{e}^{B/2}\operatorname{e}^{A/2} \ &&, \quad &&\text{(second order)}\\
& \ldots
\end{alignedat}\right.
$$
I guess, PauliTrotterEvolution
should do the job, but I have not found a tutorial.