Thermal noise reduction for future gravitational wave detectors.

Future gravitational wave detectors sensitivity is limited by specific and fundamental noises in different frequency bands. Among these, the thermal noise due to mirror coatings influences the range in which coalescence of binary systems signals accumulate, around few hundred Hz. For this reason, it is fundamental to increase the mechanical performances of these reflective coatings, retaining their outstanding optical and morphological properties. In view of future upgrades of the detectors, in Virgo and LIGO collaborations a big effort is done on many issues (like metrology, new materials, deposition parameters) to reduce this kind of noise. In this talk an overview of the ongoing activity and perspectives will be presented.