Abnormal temperature dependent elastic properties of fused silica irradiated by ultrafast lasers

Materials with thermal-invariant elastic properties are of interest for resonant device frequency and dimensional stability precision devices. Here, we demonstrate that the temperature coefficient elasticity (TCE) amorphous silica can be locally reduced using femtosecond laser irradiation. Notably, a self-organized laser-induced modification shows decrease TCE beyond 50%. The origin this dramatic is attributed to presence submicron permanent densified zones within fine multilayer structure laser-modified zone.