documentclass[aps,pra,twocolumn,showpacs,amsmath,amssymb,preprintnumbers,superscriptaddress,10pt]{revtex4-1}

usepackage{graphicx}
graphicspath{{figures/}}
usepackage{hyphenat}
usepackage{color}
usepackage{url}
usepackage[bookmarks=false]{hyperref}
usepackage[capitalise]{cleveref}
crefname{section}{Sec.}{Secs.}% APS style uses abbreviations
Crefname{section}{Section}{Sections}
usepackage[retainplus]{siunitx}
usepackage[normalem]{ulem} % for the sout command. Delete when finalized
usepackage[titletoc]{appendix}


begin{document}

begin{appendices}
    include{Appendix_A}
end{appendices}

end{document}

section{Alternate Afterpulsing algorithm}
label{appendix.AlternateAfterpulsing}

Figureref{fig.PMF} shows something.

begin{figure}
    includegraphics[width=0.90linewidth]{PMF.pdf}
    caption[content 1]{content 2}
end{figure}label{fig.PMF}