\documentclass{article}

% \usepackage{../../fiche}
\usepackage{fontspec}
\setmainfont{CMU Serif}
\setsansfont{CMU Sans Serif}
\usepackage[frenchb]{babel}
\usepackage{unicode-math}
\begin{document}

Bonjour 
α·test

$\alpha$

\end{document}