RESEARCH TRIANGLE PARK, N.C. — Army-funded research developed a new microwave radiation sensor with 100,000 times higher sensitivity than currently available commercial sensors. Researchers said better detection of microwave radiation will enable improved thermal imaging, electronic warfare, radio communications, and radar.
Researchers published their study in the peer-reviewed journal Nature. The team included scientists from Harvard University, The Institute of Photonic Sciences, Massachusetts Institute of Technology, Pohang University of Science and Technology, and Raytheon BBN Technologies. The Army, in part, funded the work to fabricate this bolometer by exploiting the giant thermal response of graphene to microwave radiation.
The graphene bolometer sensor detects electromagnetic radiation by measuring the temperature rise as the photons are absorbed into the sensor. Graphene is a two-dimensional, one-atom layer thick material. The researchers achieved a high bolometer sensitivity by incorporating graphene in the microwave antenna.
“A key innovation in this advancement is to measure the temperature rise by superconducting Josephson junction while maintaining a high microwave radiation coupling into the graphene through an antenna,” researchers said. The coupling efficiency is essential in a high-sensitivity detection because “every precious photon counts.”