Chiral metamaterial produces record optical shift under milliwatt-level power changes

April 10, 2017
Researchers have demonstrated an optical metamaterial whose chiral properties in the nonlinear optical regime produce a spectral shift with power levels in the milliwatt range.

Researchers at Georgia Institute of Technology (Atlanta, GA) have demonstrated an optical metamaterial whose chiral properties in the nonlinear optical regime produce a spectral shift with power levels in the milliwatt range. They showed properties of their chiral metamaterial in which they spectrally modified two absorptive resonances by incrementally exposing the material to power intensities beyond its linear optical regime. With a 15 mW change, they measured a 10 nm spectral shift in the material's transmission resonances and a 14° polarization rotation. The metamaterial itself was less than λ/7 thick. The researchers believe that may be the strongest nonlinear optical rotation ever reported for a chiral metamaterial, and is about 100,000X larger than the current record measurement.

The material is made by nanopatterning layers of silver approximately 33 nm thick onto glass substrates. Between the layers is a 45 nm layer of dielectric material. An elliptical pattern is created using electron-beam lithography, and then encapsulated within a dielectric material to prevent oxidation. The material operates in the visible to near-IR spectrum (740 to 1000 nm). The optical rotation and circular dichroism measurements were taken with the beam entering the material at a normal-incidence angle. This modulation of chiral optical responses from metamaterials by manipulating input power has potential in all-optical switching and light modulation. Reference: S. P. Rodrigues et al., Nature Commun. (2017); http://dx.doi.org/10.1038/ncomms14602.

About the Author

John Wallace | Senior Technical Editor (1998-2022)

John Wallace was with Laser Focus World for nearly 25 years, retiring in late June 2022. He obtained a bachelor's degree in mechanical engineering and physics at Rutgers University and a master's in optical engineering at the University of Rochester. Before becoming an editor, John worked as an engineer at RCA, Exxon, Eastman Kodak, and GCA Corporation.

Sponsored Recommendations

March 31, 2025
Enhance your remote sensing capabilities with Chroma's precision-engineered optical filters, designed for applications such as environmental monitoring, geospatial mapping, and...
March 31, 2025
Designed for compatibility with a wide range of systems, Chroma's UV filters are engineered to feature high transmission, superior out-of-band blocking, steep edge transitions...
March 31, 2025
Discover strategies to balance component performance and system design, reducing development time and costs while maximizing efficiency.
March 31, 2025
Explore the essential role of optical filters in enhancing Raman spectroscopy measurements including the various filter types and their applications in improving signal-to-noise...

Voice your opinion!

To join the conversation, and become an exclusive member of Laser Focus World, create an account today!