Physics Chat
The effects of picosecond laser machining on the optical properties of cuprous oxide
Speaker: Sam Gavin-Pitt (Prof Wolfgang Langbein's group)
Date: Thursday 5 October 2023
Time: 14:00
Venue: Queen's Building Room N/2.05
Picosecond laser pulses at energies on the scale of ~1 uJ have been used to machine defects into various samples of cuprous oxide, both natural and synthetic. Analysis techniques such as CCD spectrometry, Raman spectrometry, qDIC, and FIBSEM have all been used to investigate what effects laser machining has had on the optical properties of the crystals. The results show clear, localised damage to the crystal in the shape of a thin laser filament. This is accompanied by small changes in the band gap energy - both positive and negative - in the sample surrounding the damage as well as the introduction of split copper vacancies (also referred to as Cu3O2 defect structure in the literature). Birefringence patterns are also evident in qDIC images.