High-resolution light-field imaging via phase space retrieval.

By combining a high-resolution image from a standard camera with a low-resolution light-field image from a lenslet array, we numerically reconstruct a high-resolution light-field image. We experimentally demonstrate the method by creating a high-definition 3D image of a human cheek cell with a commercially available microscope.

Enhancing layered 3D displays with a lens.

We augment layered three-dimensional (3D) displays using a lens placed in front of or between attenuation layers. The lens, or similar optical element, improves the angular resolution of the system and enables translation of the displayed scene from a near-field image to a far-field projection. We analyze the relation between angular resolution (scene depth) and the number of layers and characterize the phase-space trade-offs between spatial and angular frequency components. We also introduce an algorithm for determining the layers of the display, which significantly reduces the computational requirements. The method is demonstrated on a standard 4D light field scene.

Wave tunneling and hysteresis in nonlinear junctions.

We consider the nonlinear tunneling of a plane wave through a small barrier potential in a medium with self-defocusing, or repulsive, interactions. We show that nonlinearity can either suppress or enhance transmission rates, determined by whether the initial kinetic energy is above or below the barrier height. Associated with this threshold is the appearance of two distinct hysteresis loops, going clockwise or counterclockwise, respectively. Spatial dynamics upon reflection and transmission reveals the formation of dispersive shock waves (dark soliton trains) due to phase jumps at the interfaces and wave steepening during propagation. The results are demonstrated experimentally for optical wave tunneling through a refractive index defect but will hold for any Schrödinger system that contains a nonlinear junction.