[Tex/LaTex] Double Subscript in Math Mode

amsmathmath-modesiunitxsubscripts

\usepackage{amsmath}
\usepackage{siunitx}
\begin{equation}
    2I_{x}S_{z} \overset{\ang{90} \text{Pulse_{I_y}}}}{\rightarrow}
\end{equation}

For some reason this is not working. For the overset text, I want a double subscript.
Thank you.

Best Answer

You can't use _ in the argument to \text. You should better use \mathrm and \xrightarrow:

\documentclass{article}
\usepackage{amsmath}
\usepackage{siunitx}

\begin{document}

\begin{equation}
2I_{x}S_{z} \xrightarrow{\ang{90}\ \mathrm{Pulse}_{I_y}}
\end{equation}

\end{document}

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