Simon Huang

Optimal control of the ballistic motion of Airy beams

We demonstrate the projectile motion of two-dimensional truncated Airy beams in a general ballistic trajectory with controllable range and height. We show that the peak beam intensity can be delivered to any desired location along the trajectory as well as repositioned to a given target after displacement due to propagation through disordered or turbulent media.

Trapping and transporting aerosols with a single optical bottle beam generated by moiré techniques

We demonstrate optical trapping and manipulation of aerosols with an optical bottle beam generated by the moiré techniques. We observe stable trapping and back-and-forth transportation of a variety of absorbing carbon particles suspended in air, ranging from clusters of nanosized buckminsterfullerene C₆₀ to micrometer-sized carbon powders.

Persistence and breakdown of Airy beams driven by an initial nonlinearity.

We study the behavior of Airy beams propagating from a nonlinear medium to a linear medium. We show that an Airy beam initially driven by a self-defocusing nonlinearity experiences anomalous diffraction and can maintain its shape in subsequent propagation, but its intensity pattern and acceleration cannot persist when driven by a self-focusing nonlinearity. The unusual behavior of Airy beams is examined from their energy flow as well as the Brillouin zone spectrum of self-induced chirped photonic lattices.

Generation and nonlinear self-trapping of optical propelling beams

We generate optical beams with rotating intensity blades by employing the moiré technique. We show that the number of the blades and the speed and direction of rotation can be controlled at ease with a spatial light modulator, while no mechanical movement or phase-sensitive interference is involved. By applying a noninstantaneous self-focusing nonlinearity, we demonstrate both theoretically and experimentally self-trapping of such optical propelling beams.

Trapping and rotating microparticles and bacteria with moiré-based optical propelling beams

We propose and demonstrate trapping and rotation of microparticles and biological samples with a moiré-based rotating optical tweezers. We show that polystyrene beads, as well as Escherichia coli cells, can be rotated with ease, while the speed and direction of rotation are fully controllable by a computer, obviating mechanical movement or phase-sensitive interference. Furthermore, we demonstrate experimentally the generation of white-light propelling beams and arrays, and discuss the possibility of optical tweezing and particle micro-manipulation based on incoherent white-light rotating patterns.

Rotating Beads and Bacteria with Moiré-Based Optical Tweezers

Since Ashkin’s pioneering work, optical trapping and manipulation have been of great interest to the optical community. Researchers have proposed many techniques for optically rotating trapped particles, but most relied on either mechanical instruments or phase-sensitive interference, which is susceptible to ambient perturbations. Recently, we demonstrated an approach for generating rotating intensity blades using the moire technique. Our propeller-like beams can be generated with variable speed and direction of rotation without requiring mechanical movement or optical interference. Furthermore, they can achieve dynamic control of trapped microparticles and bacteria.

Trapping and manipulating aerosols with optical bottle beams generated by Moiré technique

We demonstrate optical trapping and manipulation of C60 nano-aerosols with optical bottle beams. This method based on the Moiré technique can be used for trapping a variety of absorbing nano-particles suspended in air.

Nonlinearity-controlled reshaping and anomalous diffraction of Airy beams

Two-dimensional Airy beams controlled with self-focusing and self-defocusing nonlinearities exhibit unexpected behavior in free-space and scattering media, including stagnation and anomalous diffraction, and resistance to vibration and distortion, solely depending on the initial control.

Observation of Interaction and Circular Motion of Solitons in Bessel-Like Ring Lattices

We demonstrate particle-like soliton interaction and rotation in Bessel-like photonic lattices. Attractive and repulsive rotations as well as planet-like orbiting of two solitons were observed with different initial phase relations.

Linear guidance of dipole modes in an optically induced ring lattice with a low-index core

Linear guidance of dipole modes in an optically induced ring lattice with a low-refractive-index core is demonstrated both theoretically and experimentally. These dipoles are guided in the low-index region of the lattice. Such guidance results from anti-resonance or bandgaps in waveguides rather than the total internal reflection.