Harvard College

Romain Blanchard

Federico Capasso

Nanfang Yu

Mikhail A Kats

Patrice Genevet

A spectral encoder includes a thin layer of lossy dielectric material whose thickness varies transversely from 0 to a thickness of about &#x3bb;/4n (e.g., &#x3c;100 nm), where &#x3bb; is the wavelength of incident radiation and n is the dielectric material's refractive index. The dielectric layer reflects (and/or transmits) light at a wavelength that depends on the layer's thickness. Because the dielectric layer's thickness varies, different parts of the dielectric layer may reflect (transmit) light at different wavelengths. For instance, shining white light on a dielectric layer with a linearly varying thickness may produce a rainbow-like reflected (and/or transmitted) beam. Thus, the spectral encoder maps different wavelengths to different points in space. This mapping can be characterized by a transfer matrix which can be used to determine the spectrum of radiation incident on the spectral encoder from the spatial intensity distribution of the radiation reflected (and/or transmitted) by the spectral encoder.

Ultra-thin optical coatings and devices and methods of using ultra-thin optical coatings

A radiation-emitting device (e.g., a laser) includes an active region configured to generate a radiation emission linearly polarized along a first polarization direction and a device facet covered by an insulating layer and a metal layer on the insulating layer. The metal layer defines an aperture through which the radiation emission from the active region can be transmitted and coupled into surface plasmons on the outer side of the metal layer. The long axis of the aperture is non-orthogonal to the first polarization direction, and a sequential series of features are defined in or on the device facet or in the metal layer and spaced apart from the aperture, wherein the series of features are configured to manipulate the surface plasmons and to scatter surface plasmons into the far field with a second polarization direction distinct from the first polarization direction.

Growing community of inventors

Cambridge, MA, United States of America

Romain Blanchard