Researchers at the University of Witwatersrand used the geometric phase of a laser pointer to achieve for the first time a method of changing the orbital angular momentum of a laser beam. “Nature Photonics” NaturePhotonics magazine published the research results of this new type of laser discovered by researchers in South Africa and Italy, which can produce a “twisted” laser beam as its output.
The laser output and a group of laser beams formed by the new laser are superimposed, which is called a vector vortex beam. It is the first time that the geometric phase in a laser is used. This work has opened the way for the study of new lasers in applications such as optical communications, laser processing, and biomedicine.
This idea was conceived by Professor Andrew Forbes of the University of Witwatersrand (WITS), and he also led the entire collaborative research. At the same time, all key experiments were conducted by the Council for Scientific and Industrial Research (CSIR). ) Performed by Dr. Darryl Naidu.
Team members Professor Steve Lu, Dr. Angela Dudley and Dr. Igor Little contributed significantly to this work. Custom geometric phase optics. Without this concept, the realization of the experiment would be impossible. This was proposed by the research team of the University of Naples in Italy, including Professor Lorenzo Marucci and Professor Bruno Piccillo .
We are all familiar with the angular momentum in daily life: spin angular momentum of the rotating green laser pointer earth, orbital angular momentum (OAM) around the earth. Light can also carry angular momentum: through its polarization (spin), and through its mode and phase orbital angular momentum.