Time-of-flight 3D imaging through multimode optical fibers.

Time-of-flight three-dimensional (3D) imaging has applications that range from industrial inspection to motion tracking. Depth is recovered by measuring the round-trip flight time of laser pulses, typically using collection optics of several centimeters in diameter. We demonstrate near–video-rate 3D imaging through multimode fibers with a total aperture of several hundred micrometers.

Single-pixel imaging using caustic patterns.

Single-pixel imaging uses a time-varying transmission mask placed in the illumination to achieve imaging without the use of detector arrays. While most research in this field uses sophisticated masks implemented using spatial light modulators, such methods are not available at all lengthscales and wavelengths of illumination. Here we show that alternatively a sequence of projected caustic intensity patterns can be used as the basis for the single-pixel imaging of objects.

Ultra-thin transmissive crystalline silicon high-contrast grating metasurfaces.

Dielectric metasurfaces made from crystalline silicon, titanium dioxide, gallium nitride and silicon nitride have developed rapidly for applications in the visible wavelength regime. High performance metasurfaces typically require the realisation of subwavelength, high aspect ratio nanostructures, the fabrication of which can be challenging. Here, we propose and demonstrate the operation of high performance metasurfaces in ultra-thin (100 nm) crystalline silicon at the wavelength of 532 nm.

Optical trapping with planar silicon metalenses.

Contactless manipulation of micron-scale objects in a microfluidic environment is a key ingredient for a range of applications in the biosciences, including sorting, guiding, and analysis of cells and bacteria. Optical forces are powerful for this purpose but, typically, require bulky focusing elements to achieve the appropriate optical field gradients. To this end, realizing the focusing optics in a planar format would be very attractive and conducive to the integration of such microscale devices, either individually or as arrays.

An Organic Vortex Laser.

Optical vortex beams are at the heart of a number of novel research directions, both as carriers of information and for the investigation of optical activity and chiral molecules. Optical vortex beams are beams of light with a helical wavefront and associated orbital angular momentum. They are typically generated using bulk optics methods or by a passive element such as a forked grating or a metasurface to imprint the required phase distribution onto an incident beam.