Email Print Share

News Release 07-136

Photonic Gel Films Hold Promise

Sensors, display devices and tunable lasers could benefit

photonic gel crystals

Photonic gel crystals reflect light based on the way their molecules are "tuned."

October 21, 2007

This material is available primarily for archival purposes. Telephone numbers or other contact information may be out of date; please see current contact information at media contacts.

By alternating layers of two different polymers - one rigid and glassy, the other soft and easily swollen with liquid or vapor - researchers funded by the National Science Foundation (NSF) report they've created photonic gel crystals that can be tuned to reflect light of many different colors across the visible and near-infrared spectrum.

The research results, reported in the Oct. 21 online issue of Nature Materials by Principal Investigator Edwin Thomas and his colleagues at the Massachusetts Institute of Technology's department of materials science and engineering, demonstrate the degree to which these photonic materials are tunable through changes in the soft layer's thickness and index of refraction. The responsiveness of the photonic crystals makes them likely candidates for active components of display, sensory or telecommunication devices.

"This is an ingenious and easy-to-implement method for making photonic materials whose optical properties can be readily tuned over a wide range [of the spectrum]," said Andrew Lovinger, director of the polymers program at NSF, which funded this research.

In one example, the researchers show very large, reversible optical changes by varying the salt content of a water solution in which these films are dipped. Multicolor patterns can be made by sequential coating of films, with the color of each region depending on the degree to which their molecules are chemically interconnected.

"We expect these photonic gels will lead to many novel applications, including colorimetric sensors, active components of simple display devices, and electrically controlled tunable optically pumped lasers, photonic switches and multiband filters," Thomas said.

NSF funded the research in 2003 through a three-year grant aimed at creating new nanomaterials that are tunable through magnetic, chemical or other techniques. Following the discovery of intriguing new effects by Thomas and his colleagues involving the interaction of light and sound in these nanomaterials, his grant was extended for two additional years through a "special creativity award."


Media Contacts
Diane E. Banegas, NSF, (703) 292-8070, email:
Anne Trafton, Massachusetts Institute of Technology, (617) 253-6936, email:

Program Contacts
Andrew Lovinger, National Science Foundation, (703) 292-4933, email:

Principal Investigators
Edwin Thomas, Massachusetts Institute of Technology, 617-253-6901, email:

The U.S. National Science Foundation propels the nation forward by advancing fundamental research in all fields of science and engineering. NSF supports research and people by providing facilities, instruments and funding to support their ingenuity and sustain the U.S. as a global leader in research and innovation. With a fiscal year 2022 budget of $8.8 billion, NSF funds reach all 50 states through grants to nearly 2,000 colleges, universities and institutions. Each year, NSF receives more than 40,000 competitive proposals and makes about 11,000 new awards. Those awards include support for cooperative research with industry, Arctic and Antarctic research and operations, and U.S. participation in international scientific efforts.

mail icon Get News Updates by Email 

Connect with us online
NSF website:
NSF News:
For News Media:
Awards database:

Follow us on social
Twitter: and