A team of researchers from the Institute of Photonic Sciences (ICFO) and Yale University used graphene to convert light into electrical signals at room temperature.
Detecting infrared light is important in spectroscopy, materials processing, bio-molecular and sensing, and the security industry. It’s important because vibrational transitions and rotational excitations of molecules occur in the mid-infrared spectral region.
These molecules need to be monitored by observing the absorption of light in the mid-infrared region. The current detectors are inefficient for this purpose, except the ones that work at extremely low temperatures because they incorporate superconducting elements.
The researchers from ICFO and Yale have found a solution to this problem. They demonstrated that graphene can act as efficient mid-infrared detectors while operating at room temperature.
The team showed that the collective oscillations of graphene plasmons can boost the sensitivity by using resonant coupling between mid-infrared light and those plasmons.
They fabricated a device on a CVD graphene wafer made with graphene-disk plasmonic resonators joined by quasi-1D graphene nanoribbons. Next, they shined mid-infrared light into the device and observed the excitation. They also noted the high room-temperature absorption of IR plasmons on the surface of the graphene resonators and nanoribbons.
The experiment showed that the graphene nanostructures helped absorb the light and converted it to electrical responsivity.
The results proved that graphene is an excellent material to quickly convert light to electrical signals, and that too, at room temperature. This technology can be used to make tiny detectors that can be integrated into high-resolution, mid-infrared cameras and high-density integrated infrared photonic circuits used for security and air-quality monitoring.
Graphene, often referred to as a super material, is gaining popularity in many industries. Global Market Insights predicts that the graphene market will cross $200 million by 2024.
The report suggests that graphene’s increasing use in the automotive and aerospace industries will primarily drive the growth, but other industries will contribute too.
News source: graphene-info