Mode Sorters are devices that can decompose an arbitrary optical field into a complete set of orthogonal modes. A specific example of a mode sorter is a device that can decompose a light field into the members of the Laguerre-Gauss modes. Mode sorting is an enabling technology for many applications in photonics, such as optical communication, which has been our primary interest. For technical reasons, it is more difficult to construct mode sorters for some degrees of freedom than for others; for example, it is more difficult to decompose into the radial Laguerre-Gauss modes than into its azimuthal modes. In earlier work, we showed how to construct a radial mode sorter [1]. In the past year we extended this work by constructing a mode sorter for all transverse degrees of freedom of a light field and using this device in a quantum communication system [2].
- Sorting Photons by Radial Quantum Number, Y. Zhou, M. Mirhosseini, D. Fu, J. Zhao, S. M. H. M. Rafsanjani, A. E. Willner, and R. W. Boyd, Phys. Rev. Letters 119, 263602 (2017).
- Using all transverse degrees of freedom in quantum communications based on a generic modesorter, Y. Zhou, M. Mirhosseini, S. Oliver, J. Zhao, S. M. H. Rafsanjani, M. P. J. Lavery, A. E. Willner, and R. W. Boyd, Optics Express 27, 10383-10394 (2019). (Designated as an Editor’s Pick.)