The light field with special designed spatial structure has important applications in particle manipulation, information/energy transmission, optical storage, micro-nano optical device fabrication, and photonic lattice fabrication. This direction mainly focuses on how to design a special structured light field, how the light propagates in space, and how to use such structured light field to make micro-nano structure photonic lattices in glass or nonlinear crystals.
The light field and photon lattice images we designed or fabricated in the experiment are shown below.
Fig. 1. (a). Fabrication of periodic light field and corresponding photonic lattice in nonlinear crystal using digital holography technology.
We fabricated (1) octagonal and dodecagonal light field and corresponding photonic lattices, and studied the phenomena of nonlinear transmission and pseudo-spin of such trutured light fields [Optical Materials Express, 2018, 8(9): 2713-2721]; (2) Arrays of Airy, Bessel and Vortex light field were designed, and the corresponding complex photonic lattice was fabricated by using the digital holography and photorefractive nonlinear effect, as shown in Figure 1[Optics Communications, 2016, 363: 85-90] . The article was selected by Anna Peacock, editor of Optics Communications, a classic journal in the field of optics, to be highlighted and nominated in early December 2017, and provided a three-month free promotional visit. (3) We fabricated two-dimensional photoinduced photonic lattices in iron-doped lithium niobate (LiNbO3:Fe) crystals based on nonlinear effects using the interference method, and observed the soliton and spectrum in such photonic lattice [Applied Physics Letters, 2007, 91(13): 131111].
(b). Surface mode in curved photonic lattice
The part of work was done in Professor Yuri Kivshar 's group at the Australian National University. We design a cosine-shaped curved waveguide with a period of 14 μm and an amplitude from 21.5 μm to 24.5 μm. Such waveguide arrays was fabricated in a 50 mm long lithium niobate crystal sheet with a high-temperature titanium diffusion process, as shown in Figure 2 . Except the surface defect, such a structure is modulated periodically in the z direction, such structure can be used to support the surface modes and can also be used to achieve the dynamic location. Related work was published in Optics Letters, 2009, 34(18): 2751-2753, Optics Letters, 2010, 35(9) : 1371-1373, Photonics and Nanostructures-Fundamentals and Applications, 2010, 8(2): 62-66.
Fig. 2. Schematic of the curved photonic lattice fabricated by the titanium diffusion method in lithium niobate crystal and the linear mode of surface defects [left side: Optics Letters, 2009, 34(18): 2751-2753].