the limit arrow: its label too high

Question

My question is an extension of this one. I have the command

\documentclass{article}
\usepackage{amsmath}
\begin{document}
$a_n \xrightarrow{\scriptscriptstyle n\to\infty} 0$ 
\end{document}

which produces .

How can I alter this command (hopefully in a simple way) to get , i.e. the label is closer to the arrow, so the command doesn't produce ugly additional space between rows.

Answer 1

This is an ugly hack, but it does seem to work:

$a_n \xrightarrow{%
         \raisebox{-2pt}[0pt][0pt]{%
             \ensuremath{\scriptscriptstyle n\to\infty}}} 0$

If you want it to work more generally, you can throw something together using \mathchoice I presume.