@article{oai:nifs-repository.repo.nii.ac.jp:00011188,
 author = {TSUJIMURA, Ii Toru and GOTO, Yuki and OKADA,  Koji and KOBAYASHI,  Sakuji and KUBO,  Shin},
 issue = {4},
 journal = {Review of Scientific Instruments},
 month = {Apr},
 note = {0000-0002-2983-5920, In this paper, we report the development of off-axis spiral phase mirrors that can be used to generate optical vortices from a range of millimeter waves. An obliquely incident Gaussian beam is reflected from a spiral phase mirror and is converted into an optical vortex beam with a desired topological charge. The mirrors were fabricated by mechanical machining. The designed vortex properties of reflected waves were investigated experimentally by using a low-power test, where the designed topological charge was verified based on the interference pattern between a vortex beam and a Gaussian-like beam. The designed topological charge was also estimated by using a phase retrieval method specialized for a vortex beam. These off-axis spiral phase mirrors can be used for propagation experiments of radio frequency waves with helical wavefronts in magnetized plasma.},
 title = {Development of off-axis spiral phase mirrors for generating optical vortices in a range of millimeter waves},
 volume = {93},
 year = {2022}
}