
\documentclass{article}
  \usepackage{tikz}
  \pagestyle{empty}

\begin{document}
\begin{tikzpicture}
\draw[line width=.8pt,->] (0cm,0pt) -- ++(5.5cm,0pt) ;
\foreach \x in {0,0.5,...,5.0} \draw (\x cm,4pt) -- (\x cm,-4pt) node[anchor=north,font=\footnotesize\it] {\x} ;
\end{tikzpicture}
\end{document}
