Two-Dimensional Maxwell Fisheye for Integrated Optics

Maxwell invented a refractive-index profile where light goes in circles and every point is focused. A device with such a profile is called the Maxwell fisheye and it is an absolute optical instrument: it has the ability to collect all rays from any emitting source and recombine them in phase at the corresponding focal point inside the device. Absolute optical instruments may find diverse applications if they can be made in integrated optics on a silicon chip for infrared light. We have fabricated the Maxwell fisheye in silicon photonics and have demonstrated its focusing properties. Our fabrication technique can also be applied to the manufacturing of other devices where smooth and sharp structures need to be made in one lithography step.