Novel color photography using a high-efficiency probe can super-focus white light into a 6-nanometer spot for nanoscale color imaging

About this Project

With my colleagues from UC Riverside, I have developed a revolutionary imaging technology that compresses lamp light into a nanometer-sized spot. It holds that light at the end of a silver nanowire like a Hogwarts student practicing the "Lumos" spell, and uses it to reveal previously invisible details, including colors.

The advance, improving color-imaging resolution to an unprecedented 6 nanometer level, will help scientists see nanomaterials in enough detail to make them more useful in electronics and other applications. This work has been published on Nature Communications and has also been highlighted in the collections of 2021 Top 25 Chemistry and Materials Sciences Article and 2021 Top 25 Physics Articles.

Abstract

Optical transmission and scattering spectroscopic microscopy at the visible and adjacent wavelengths denote one of the most informative and inclusive characterization methods in material research. Unfortunately, restricted by the diffraction limit of light, it cannot resolve the nanoscale variation in light absorption and scattering, diagnostics of the local inhomogeneity in material structure and properties. Moreover, a large quantity of nanomaterials has anisotropic optical properties that are appealing yet hard to characterize through conventional optical methods. There is an increasing demand to extend the optical hyperspectral imaging into the nanometer length scale. In this work, we report a super-resolution hyperspectral imaging technique that uses a nanoscale white light source generated by superfocusing the light from a tungsten-halogen lamp to simultaneously obtain optical transmission and scattering spectroscopic images. A 6-nm spatial resolution in the visible to near-infrared wavelength regime (415–980 nm) is demonstrated on an individual single-walled carbon nanotube (SW-CNT). Both the longitudinal and transverse optical electronic transitions are measured, and the SW-CNT chiral indices can be identified. The band structure modulation in a SW-CNT through strain engineering is mapped.



Contribution

I am credited as the first author of this article for a four-year devotion of my work to the experiments that made this advance possible. My technique opens the door for the color photography of the nano-world, which is much more fascinating than the macro-world. With this work, I achieved the first-ever color photo of the single-walled carbon nanotube, which is known as one of the blackest materials.