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Electro-optic spatial light modulator from a single organic layer

October 14, 2021

Spatial light modulators (SLM) provide tailored light fields for many applications. Here, we show that an SLM device can be realized from a structure as simple as a single organic electro-optic material deposited on top of interlaced gold electrodes. When we apply an electric signal across these electrodes, the refractive index of the electro-optical film changes. By nanoscale engineering of the nonlinear properties of the material and electrodes, we demonstrate modulation of the intensity of light at speeds up to 50 MHz, with tiny microwatt-level switching electrical...

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A high aspect ratio holey metalens

A high aspect ratio holey metalens

October 13, 2021

Multiple beneficial optical device properties scale with the thickness of nanostructures. For example, taller nanostructures afford a greater degree of control over multiple colors of light, expanding the range of chromatic behaviors and possibly leading to large-area achromatic metalenses. However, in conventional meta-optics, which employ free-standing nanopillars or nanofins, increasing the nanostructure height while maintaining subwavelength nanostructure spacing requires high aspect ratio structures (aspect ratio = height to width ratio), which are difficult to fabricate and work...

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Jones matrix holography

Metasurfaces control polarized light at-will

August 16, 2021

In recent years, considerable attention has been paid to the ability of metasurface optics to manipulate polarized light. A variety of works and applications have been demonstrated showing, for instance, how metasurfaces can create optics with different behaviors that switch on the basis of light's polarization state, or that produce polarized holograms.

In recent work published in Science Advances, we show that a new perspective - which we dub "Jones matrix holography" - generalizes much of this past work and suggests new possibilties as well that exceed the level of...

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One metasurface to rule them all

One metasurface to rule them all

July 12, 2021

It typically takes several independently-controlled components to fully manipulate the various degrees of freedom (e.g. wavelength, shape, and power) of a laser beam. In this publication, we show that a single reflective metasurface and a laser diode can exert full control of the shape and intensity of diffraction orders. The design does not require any rotating components and is compact. The research has applications in quantum sensing and virtual reality/augmented reality (VR/AR) headsets. 

Check out the publication in...

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heart shaped phase singularity

Harnessing the dark side with optical singularities

July 12, 2021

Do black holes come to mind when you think about singularities? In optics, singularities occur when one or more parameters are undefined, and are also associated with non-intuitive phenomena such as energy backflow and superoscillations. While the vast majority of optical singularities take the form of string-like lines and loops, this paper introduces a technique to engineer singularities belonging to a wider class of shapes. As a demonstration, the authors engineer sheet singularities that have heart-shaped cross-sections, then realize these light fields experimentally using...

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