Dissipation of micro-cantilevers as a function of air pressure and metallic coating

Abstract

In this letter, we characterize the internal dissipation of coated\nmicro-cantilevers through their mechanical thermal noise. Using a home-made\ninterferometric setup, we achieve a resolution down to 1E-14m/rtHz in the\nmeasurement of their deflection. With the use of the fluctuation dissipation\ntheorem and of the Kramers-Kronig relations, we rebuilt the full mechanical\nresponse function from the measured noise spectrum, and investigate frequency\ndependent dissipation as a function of the air pressure and of the nature of\nthe metallic coatings. Using different thicknesses of gold coatings, we discuss\nthe source of the internal viscoelastic damping.\n