High Intensity Laser Irradiation of Solid Targets at a High Repetition Rate


  Dolev Roitman  ,  Itay Kishon  ,  Ishay Pomerantz  
School of Physics and Astronomy, Tel-Aviv University, Israel

Current solid-target positioning systems for high-intensity ultra-short pulsed laser experiments lack the ability to perform at high rates. We are developing a target manipulation system that will enable solid target irradiation at a 10 Hz rate. The system will allow collecting data that incorporates a large number of laser shots at fixed experimental conditions that leads to high overall radiation dose and increased statistics.

The manipulation system utilizes a closed loop feedback control to automatically place a solid target at the focus of the laser with sub-wavelength accuracy.

A major design challenge is the Electromagnetic Pulse (EMP) generated by the laser-plasma interaction. Positioning systems designed with encoders cannot withstand the EMP. Hence, in our system, the target position is measured using a laser displacement sensor which provides sub-wavelength resolution.

The mechanical assembly consists of high accuracy Piezo motors and a laser displacement sensor that feeds back to a closed loop system. A Silicon wafer that holds up to 10,000 targets can be mounted on the target system to allow 20 minutes of irradiation at a rate of 10 Hz.

I will present the design, preliminary performance measurements and our future plans.