# Labelling qcircuit

I am trying to add an EPR pair to a quantum circuit as an entry, and I need to select both of the entries using a bracket ({) that takes both of the entries. I am interested in that the output is something such as

I am using Qcircuit in order to perform the task, I haven't been able to find how to do this.

## 1 Answer

You need the \gategroup command. The following code should do what you want:

\documentclass{standalone}
\input{Qcircuit}% using  qcircuit version 2.5
\begin{document}
\begin{tabular}{c}
\vspace{-.6em}\\
\hspace{1.5em}
\Qcircuit @C=1em @R=2em @!R {
& \lstick{\ket{\psi}} & \qw & \qw \\
& & \qw & \qw \\
& \lstick{\raisebox{2.2em}{$\ket{\beta_{00}}$\ }} & \qw & \qw
\gategroup{2}{2}{3}{2}{.8em}{\{}
}
\vspace{2em}\hspace{1em}
\\
\end{tabular}
\end{document}


It produces the output below: