Conference paper
SLM phase mask optimization for fiber OAM mode excitation
Fiber Optics, Devices and Non-linear Effects, Department of Photonics Engineering, Technical University of Denmark1
Networks Technology and Service Platforms, Department of Photonics Engineering, Technical University of Denmark2
Department of Photonics Engineering, Technical University of Denmark3
Programmable Phase Optics, Department of Photonics Engineering, Technical University of Denmark4
Fiber orbital angular momentum (OAM) modes can be employed in mode-division multiplexing to increase the channel capacity in optical communication systems. Over the years, several experiments to excite high-purity OAM modes by using one phase-only spatial light modulator (SLM) have been conducted. Since phase-only SLMs are intrinsically imperfect for this purpose due to the impossibility to simultaneously modulate both amplitude and phase in the light source, optimal phase masks need to be generated by iterative algorithms.
However, if the state of every pixel in the mask is an unknown of the problem, the computational cost is extremely high. The system circular symmetry can be exploited to overcome this issue. Here, for the first time, this approach is implemented and a simple machine learning algorithm is developed to calculate optimal phase masks with a low number of unknowns and iterations.
Simulated and experimental results show that the developed technique is capable of exciting high-purity OAM modes.
| Language: | English |
|---|---|
| Publisher: | SPIE - International Society for Optical Engineering |
| Year: | 2019 |
| Pages: | 109350F-109350F-8 |
| Proceedings: | Complex Light and Optical Forces XIII |
| Series: | Proceedings of Spie - the International Society for Optical Engineering |
| ISBN: | 1510625127 , 1510625135 , 9781510625129 and 9781510625136 |
| ISSN: | 1996756x and 0277786x |
| Types: | Conference paper |
| DOI: | 10.1117/12.2507424 |
| ORCIDs: | Astorino, Antonio and Rottwitt, Karsten |
