\documentclass[preview,convert={indir={aux/}, outdir={aux/}, outputdir={aux/}},border=40px]{standalone}
\usepackage{quantikz}

\begin{document}
\begin{quantikz}
\lstick[2]{$\ket{\varphi}$} & \ctrl{1} & \targ{}  & \ctrl{1} & \rstick[2]{$\ket{\varphi'}$}\\
                            & \targ{}  & \ctrl{-1}& \targ{}  &
\end{quantikz}
\hspace{1cm}
\end{document}