Electrohydrodynamics pump and machine learning enable portable high-performance lasers

According to a recent study published in APL Photonicsa research team led by Professor Liang Xu from the Hefei Institute of Physical Science of the Chinese Academy of Sciences has developed an ultra-compact excimer laser roughly the size of a thermos bottle.

Excimer lasers are important sources of deep ultraviolet light and are widely used in scientific research, industrial processing, and environmental monitoring. However, conventional systems rely on mechanical gas pumps for medium circulation, resulting in large size, noise levels and significant vibration. These limitations limit their application in field environments, marine exploration, and airborne platforms.

To solve these problems, the researchers replaced the mechanical pumps with multi-needle corona discharge electrohydrodynamics (EHD) pumps. This eliminated the need to move parts and reduced the system’s volume to 130 mm × 300 mm. Using a self-developed, non-invasive point Schlieren velocimetry technique, the researchers measured a gas flow velocity of 1.27 m/s inside the laser cavity.

Operating at 100 Hz, the system achieved a gas refresh rate of 6.35, delivering pulse energies in excess of 2 mJ while maintaining exceptional energy stability, with a relative standard deviation of less than 1%.

The researchers also observed a unique explosive transition behavior in the laser pulse energy under certain conditions. Through analysis of the complex photochemical reactions of the XECL excimer network, they discovered that this phenomenon is associated with a threshold-driven burst in photon flux, revealing the microscopic mechanism behind shifts in macroscopic laser efficiency.

Additionally, the team developed an interpretive machine learning model capable of predicting energy transfer across a wide range of operating parameters.

This study provides valuable support for optimization and control of ultra-compact excimer laser systems in practical applications.