\documentclass{standalone}
\usepackage{tikz}
\usetikzlibrary{decorations.pathreplacing,decorations.pathmorphing}
\usetikzlibrary{fit,quotes}
\usepackage{yquant, braket}
\input{utils}

\begin{document}
\begin{tikzpicture}
  \begin{yquant}
    qubit[2] q;
    cnot q[1] | q[0];
    hspace {3mm} q;
    [name=del, x radius=12mm] box {$Delay [30ns]$} q[0];
    [x radius=12mm] box {$R_Y(\pi/2)$} q[1];
    hspace {3mm} q;
    cnot q[1] | q[0];
    [name=rz] box {$R_Z(\pi/4)$} q[0];
  \end{yquant}
  \draw [line width=1pt, ->, dashed] ([yshift=1mm, xshift=-2mm]rz-0.north west) to [bend right] ([yshift=1mm, xshift=2mm] del-0.north east);
\end{tikzpicture}
\end{document}
