Effect of a fiber-capillary structure on nanosecond laser pulse propulsion

In the propulsion experiments, we investigate the effect of the micro propulsion structure on laser pulse propulsion. A single glass microsphere with diameter of 60 μm used as a projectile was deposited into the capillary tube. In the collected spectra, several characteristic peaks appeared, demonstrating that plasma formation due to air ionization. The simulation results showed that the capillary can reduce the loss of laser pulse energy and confines a portion of the pulse energy in the micro propulsion structure (the micro propulsion structure consists of a fiber and capillary). The shockwave formation due to the plasma expansion was oriented along the laser propagation direction. Therefore, the propulsion efficiency can be enhanced.