Symbol: "maps isomorphically" [duplicate]

Question

I want to make a symbol for "maps isomorphically" which consists of a relatively large tilde above a right arrow. Overset doesn't work (besides, the tilde would be too small). MWE:

\documentclass{article}
\usepackage{amsmath}

\begin{document}
Thus $X$ is isomorphic to $Y$ via $f$: 
\[f : X \overset{\tilde}{\to} Y.\]
\end{document}

I also tried using array but that didn't work either. MWE:

\documentclass{article}
\usepackage{amsmath}

\begin{document}
Thus $X$ is isomorphic to $Y$ via $f$: 
\[f: X \begin{array}{c}\tilde \\ \to \end{array} Y\]

If I could get this to work, the spacing would need to be adjusted significantly.

Answer 1

The \xrightarrow should work as pointed out by Alex. Here is how to implement this:

\documentclass{article}
\usepackage{amsmath}

\begin{document}
{\tiny
Thus $X$ is isomorphic to $Y$ via $f$: 
\[f : X \xrightarrow{\sim} Y.\]
}
{\Large
Thus $X$ is isomorphic to $Y$ via $f$: 
\[f : X \xrightarrow{\sim} Y.\]
}
\end{document}

The output is shown for two different font sizes: