Research on plasma characteristics of fused silica induced by millisecond pulsed laser

With the continuous development of optoelectronics science, the widespread and intensive application of transparent optical elements has become an indispensable condition for the development of information technology in society. Transparent optical elements under the action of strong laser light are prone to produce plasma and even then cause damage to the elements. Therefore, it is important to study the process of interaction between transparent optical elements and strong laser light and its results. In this paper, a theoretical research and simulation study is conducted to investigate the characteristics of 1064 nm millisecond pulsed laser induced plasma generation in transparent optical elements represented by fused silica. It is demonstrated that the plasma propagation velocity and the temperature of each part increase with the increase of laser energy density during the interaction between the millisecond pulsed laser and the transparent optical elements; the plasma propagation velocity tends to increase and then decrease with the increasing of laser action time, and the temperature continues to increase near the threshold value；The plasma propagation velocity increases with the increasing of laser pulse width, and the velocity variation pattern is similar in all pulse widths; the temperature increases with the increasing of laser pulse width and approaches the temperature threshold that can be reached by the combustion wave generated by the interaction between the millisecond pulsed laser and fused silica. Finally, the kinetic characteristics and temperature rise phenomenon of the plasma propagation generated during the interaction between the millisecond pulsed laser and the transparent optical element are explained.