Small refractive-index variations induced as periodic arrays of evanescently coupled 1D and 2D waveguides have served as a platform for exploring many phenomena beyond optics. In this RUI research project, some fundamental issues and novel phenomena in specially-designed photonic structures with engineered coupling are being studied, including light tunneling inhibition and image transmission via coherent destruction of tunneling, negative coupling and associated phenomena, Shockley-like and topologically induced surface states in honey-comb photonic lattices and superlattices, and bandgap phenomena and light transport in disordered lattices. This project is being carried out in an optical setting of reconfigurable periodic structures, especially optically induced 2D lattices with intelligent design of coupling or longitudinal modulation and 3D photonic lattices.
Although performed in a simple optical setting, the research are expected to have direct impact on other areas of sciences, ranging from solid state physics to photonic crystals, and from hydrodynamics to atomic physics such as Bose-Einstein condensates trapped in periodic potentials. A major emphasis of this project is placed on mentoring undergraduate students, particularly those from the ethnically diverse San Francisco Bay Area population. A strong educational component of this work is that the research project is being used as a form of teaching as well as discovery, and the students are actively involved in learning research methods and in sharing discoveries and interpretations.
Small optical refractive-index variations could be introduced in otherwise uniform materials as periodic arrays of evanescently coupled waveguides, which could serve as a platform for studying many intriguing phenomena beyond optics. In this project, the optical induction technique has been employed to establish various specially designed photonic structures as a workbench for investigation some fundamental wave phenomena and their applications. These include image transmission through periodic media based on light tunneling inhibition, nontrivial surface (edge) states in honeycomb lattices, and accelerating diffraction-free beams and optical analog of Wannier–Stark beams in engineered photonic lattices. Although performed in a simple optical setting of reconfigurable photonic structures, much of our proposed work will have direct impact on other areas of sciences, ranging from solid state physics to atom physics such as Bose-Einstein condensates trapped in periodic potentials. For instance, the electronic edge states were known for decades, but such fundamental phenomena have recently attracted growing interest in optics that has led to the successful demonstration of photonic topological insulators. Indeed, this project shows that there is much potential to use optical systems as photonic simulators for studying complex classical and quantum phenomena. The experimental techniques that used in this project are straightforward so the project has involved active participation of undergraduate and master-level graduate students. The research activities bring exposure of students to a broad range of phenomena in a cutting-edge field of interdisciplinary science. In fact, throughout the project, a major emphasis has been placed on mentoring students, particularly those from the ethnically diverse San Francisco Bay Area population. Thus, an important feature of the project is the integration of research and education through training of students in a fundamentally and technologically important area.
