Structured light

14:00 Invited talk : High-Q All-dielectric Metasurfaces

Yuanmu Yang (1),Ivan I. Kravchenko (2),Dayrl P. Briggs (2),Jason Valentine (1)

(1)Vanderbilt University (USA) , (2)Oak Ridge National Laboratory (USA)

Here,we present an experimentally demonstration of a classical analogue of EIT using all-dielectric silicon-based metasurfaces. Due to extremely low absorption loss and coherent interaction of neighboring meta-atoms, a Q-factor of 483 is observed, leading to a refractive index sensor with a figure-of-merit of 103. Furthermore, we show that the silicon-based metasurfaces can be utilized for significantly enhancing nonlinear conversion.
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14:20 : Aperiodic Nanophotonics: A New Paradigm for Engineering Light's Orbital Angular Momentum

Hong Liu, Muhammad Q. Mehmood, Kun Huang, Lin Ke, Huapeng Ye, Patrice Genevet, Mingsheng Zhang, Cheng-Wei Qiu, Jinghua Teng

A*STAR (Singapore)

I would like to introduce our recent works using aperiodic nanostructures to engineer light's orbital angular momentum (OAM), which has a wide spectrum of promising applications. We propose nanostructured flat logarithmic-spiral zone plates (LSZP) to produce as well as focus optical vortices in the broadband visible range. Another work is about an analog optical vortex transmitter producing theoretically boundless quanta of OAM. This novel approach bridges the technology gap between digitalization, discretization and analog generations of optical OAM.
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14:35 Invited talk : Absorption of the Twisted Photons by Atoms

Andrei Afanasev (1),C. E. Carlson (2),A. Mukherjee (3)

(1)The George Washington University (USA) , (2)College of William and Mary (USA) , (3)Indian Institute of Technology Bombay (India)

We discuss novel features of twisted-light absorption both by hydrogen-like atoms. In particular, we extend the treatment of atomic photoexcitation by twisted photons to include atomic recoil, derive generalized quantum selection rules and consider phenomena of forbidden atomic transitions. We also suggest the measurements that demonstrate unique features of the optical vortices at the quantum level.
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14:55 Invited talk : Spin-orbit interactions of resonating metasurfaces

Xiaobo Yin

University of Colorado (USA)

The spin-orbit interaction destroys the rotational symmetry of particles' spin degree of freedom and introduces a universal transverse spin current regardless the particle nature of an electron or photon. Here we show that an optically thin metasurface refracts light anomalously and supports negative photonic spin Hall effect when a light beam is negatively refracted. Moreover, we will show how the inversion symmetry in the 2D metasurfaces plays a role and generates a new type of photonic Hall effect.
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