Research Topics and Projects
Optical manipulation of biological samples

Over the past few decades, optical manipulation research has deepened our understanding of physics and biology and has led to the development of cutting-edge optical-tweezers technology used across many branches of science. In our lab, we are developing novel optical techniques for optical trapping and control of biological samples (such as bacteria, red blood cells, and DNA molecules). These techniques are based on novel optical beams including self-propelling beams with rotating intensity blades, optical bottles, and self-accelerating nondiffraction Airy beams.
Novel phenomena in optical periodic and quasi-periodic structures

Light propagation in periodic structures exhibits many intriguing phenomena with new opportunities to control the flow of light. A typical periodic system is photonic lattices (closely-spaced waveguide arrays), which has served as a test-bench for exploring both linear and nonlinear phenomena for over a decade. We focus on the management of the diffraction and refraction of light with various reconfigurable photonic lattice structures, including square, Bessel, ionic-type lattices, as well as quasi-periodic and random photonic lattices. In nonlinear regime, we study the dynamics of different novel localized soliton states, including discrete, gap, and embedded lattice solitons.
Optical defect and surface states

One of the most fascinating features of photonic band-gap structures is that they provide a fundamentally different way of waveguiding by defects in otherwise uniformly periodic structures, as opposed to guidance by total internal reflection. We focus on the linear and nonlinear dynamics of photonic band-gap guidance of spatial frequency modes in various photonic lattices with structured defects, including PCF-like Bessel lattice, square lattice, and other lattice structures.

The field of surface science is one of the richest in physics due to the ubiquitous nature of surface phenomena. For example, electronic Tamm and Shockley surface states have intrigued scientists ever since they were first predicted, although their direct observation remained elusive for decades because of the intrinsic defects and complicated nature of real surfaces in condensed matter physics. In our lab, we study both linear and nonlinear surface states with optically-induced photonic structures, including Tamm, Shockley, and other related surface states.
Spatial optical solitons and related phenomena

Optical spatial solitons, light beams free of diverging, have been demonstrated to exhibit fascinating particle-like behavior, including fusion, fission, annihilation, stable orbiting and clustering. These solitons are promising for applications in controlling light by light and all-optical switching. We focus on novel phenomena from soliton formation, interaction, and modulation instability, especially when such solitons are made with partially incoherent light.