Preparation method for saturable absorption mirror based on large-sized graphene

The invention relates to a preparation method for a saturable absorption mirror based on a large-sized graphene. The preparation method comprises the following steps of: preparing a single layer of graphene film on a Cu foil; rotationally coating polymethylmethacrylate (PMMA) on the graphene film; after hot drying, placing into a FeCl3 solution and soaking at room temperature; cleaning; moving the graphene film and the PMMA on the graphene film to a laser high-reflectivity mirror; and blowing to the surface of the laser high-reflectivity mirror through weak airflow of an air gun. The preparation method is simple, high in efficiency, high in anti-damage threshold value and large in area. The graphene of the prepared saturable absorption mirror can maintain the integrated chemical structure and the graphene has the centimeter size.