Prof. Yoko Miyamoto
The University of Electro-Communications
Prof. Yoko Miyamoto
The University of Electro-Communications Japan
Generation and characterization of polarization structures
Optical fields with inhomogeneous polarization are a topic of recent interest due to development of various techniques to generate them in a controlled manner and applications such as polarimetry. Of special interest are fields that cover the entire Poincaré sphere, that is, all possible polarization states including ellipticity, handedness, and orientation of major axis. Here I present two very different instances of such optical fields and their characterizations.
The first instance is the phenomenon of vortex unfolding, where a singular structure in homogenous polarization, i.e. a single point on the Poincaré sphere, develops into a complex structure covering the entire sphere. The process can be characterized by the unfolding region, the real-space region over which the polarization state travels half way around the Poincaré sphere. The shape of this region can reveal the fine balance between the orthogonal polarization components.
The second instance is the non-separable beam, where different spatial modes appear depending on projection in polarization states. When such beams encounter spatially random phase modulation, the scattered field displays different degrees of spatially varying polarization states depending on the separability of the original beam. We have generated beams with controllable separability where one polarization state is a Gaussian beam and the orthogonal counterpart is a vortex beam of varying topological index. We have found that in the scattered field the polarization correlation length becomes shorter with the index while the intensity correlation length is only weakly affected.
- Y. Miyamoto and S. Vyas, Proc. SPIE 10120 (2017) 1012003.
- G. R. Salla et al., Opt. Express 25 (2017) 19886-19893.
Yoko Miyamoto is an associate professor at the Department of Engineering Science in the University of Electro-Communications, Japan. She received PhD in physics from the University of Tokyo in 1995, and joined the University of Electro-Communications in 1996. She was promoted to her current position in 2013. She
leads a group on quantum and applied optics, with research topics including orbital angular momentum photon states and their application to information technology, observation and application of singular polarization structures, and Real time 3D plofilometry. She is a member of OSA, SPIE, the Physical Society of Japan, the Japan Society of Applied Physics, and the Optical Society of Japan.