2012/05/04 by Alexander Carot, Alexander Carôt, Horst Aichmann +4
Engineering · Physics and Astronomy · #78 #Advanced Frequency and Time Standards #FOS: Physical sciences #Optics (physics.optics) #Photonic and Optical Devices #Quantum optics and atomic interactions #msc:78 #physics.optics
paper · pdf · doi:10.48550/arxiv.1205.1000
4 pages, 5 figures
arxiv created 2012/05/04 · openalex publication_date 2012/05/04 · arxiv updated 2012/05/07 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
A Fabry-Perot like interferometer with two microwaveguide adaptors as reflectors creates a passive dielectric medium with a negative group delay time due to polarization shift. A rotational strain of the polarization vector by one of the adaptors is coupled with a drastic negative group velocity. The adapted rectangular and circular waveguides have the same dispersion. The input rectangular waveguide mode is linearly polarized, whereas the basic mode of the adapted circular waveguide is circularly polarized. A 667 wavelengths long circular waveguide connects the input with the output adaptor. Experiments are performed in the frequency and in the time domain. We describe, how the helical polarization change and the spin-flip of the two different circular wave modes produce the observed negative group velocity.