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

\begin{document}
\begin{tikzpicture}
  \begin{yquant}
    qubit[3] q;
    cnot q[1] | q[0];
    [name=boxa, x radius=4mm, y radius=6mm] box {$R^+$} q[2];
    [name=boxb, x radius=8mm, y radius=6mm] box {$R^-$} q[2];
    [name=boxc, x radius=4mm, y radius=6mm] box {$R^+$} q[2];
  \end{yquant}
  \spring[4mm]{boxa}{1mm};
  \spring[4mm]{boxb}{1mm};
  \spring[4mm]{boxc}{1mm};
\end{tikzpicture}
\end{document}
