Page to describe the ASOPS laser system, its capabilities, its quirks and maintenance
switching on the system from standby mode.
switching on the system from complete power off
using the windows software for trouble shooting and tuning.
Using the system for experiments
the ASOPs lasers are used in standard pump probe setup. One laser (Laser B) is used as the pump beam. this laser is frequency doubled in a nonlinear crystal (BBO) to change the wavelength from 780nm to 390nm, As this process is not very efficient the output power of the blue beam is much lower than the input NIR beam. Typically 20mW of blue light is produced the remainder of the NIR light is removed from the beam path with a dichoric mirror and directed at 45 degrees to a beam dump.
The blue light is then focused down on to the sample. The poisiotn of the blue beam can be altered by adjusting the final mirror in the pump path. To view the blue beam on the CCD the probe beam path must be blocked. the half wave plate before the photodiode must be rotated to allow light through to the camera arm. The CCD exposure time will need to be increased to ZZZZ.