Ultrafast thermalization dynamics of gold-coated fused silica irradiated by a femtosecond laser

• The ultrafast temperature fields is predicted by FEM simulations.
• The critical thickness for gold-coated fused silica is obtained.
• The effect of gold layer thickness on thermalization of gold-coated fused silica is explored.

The ultrafast thermalization dynamics in gold-coated fused silica irradiated by femtosecond laser are numerically investigated by Finite Element Method (FEM). The temporally sequential thermal relaxation model, which jointly considers the two temperature relaxation and the thermal diffusion relaxation dynamics is proposed for explaining the thermalization characteristics in gold-coated fused silica system. It is revealed that the gold layer thickness of 0.6 μm is the critical thickness for influencing the temperature distribution across gold-coated fused silica system. In addition, the effect of gold layer thickness on thermalization dynamics of gold-coated fused silica system is examined in detail.