דף 1 מתוך 1

Topologically controlled multifunctional metasurfaces

נשלח: 10:54 08/11/2018
על ידי physics
יתר הפרטים מופיעים באתר הסמינרים ( http://in.bgu.ac.il/engn/ece/Pages/SeminarP.aspx) . ההרצאה תתקיים כמובן ביום ב' בשעה 13:00, בניין 37 אולם 202.



Topologically controlled multifunctional metasurfaces



Erez Hasman



Technion–Israel Institute of Technology, Haifa 3200003, Israel.



The photonic spin-orbit interaction manifested by two-dimensional nanophotonics based on Berry phase serves as a platform to generate different topological states. We report on photonic spin-symmetry breaking and unexpected spin-optical transport phenomena arising from subwavelength scale disordered geometric phase structure. Weak disorder induces a photonic spin Hall effect, observed via quantum weak measurements, whereas strong disorder leads to spin-split modes in momentum space, a random optical-Rashba effect. Study of the momentum space entropy reveals an optical transition upon reaching a critical point where the structure’s anisotropy axis vanishes. Moreover, we observed a topological phase transition from binding vortex pairs to unbinding vortices which results in a spin-optical transition from photonic spin Hall effect to random Rashba effect, emerging from a metasurface. This is achieved by implementing geometric phase point-defects in a metasurface inducing the transition from quasi long-range order to short-range order. These experiments are paving the way for the exploration of peculiar phenomena in quantum topological phase transition via metasurfaces involving spin-orbit interaction.