Researchers from USTEM have proven, that Cerenkov radiation can be utilized for the determination of refractive indices by using electron microscopy and a radiation detector. In the present study fast electrons were accelerated towards an MgO specimen, thus generating Cerenkov radiation inside the speciman. "The specimen itself acts as a Fabry-Perot interferometer", explains Dr. Michael Stöger-Pollach, group leader and author of the study. "Measuring the interference pattern with an accurate knowledge of the sample thickness can then be utilized for the accurate determination of the refractive index," he says. "This method opens the door for the exploration of optical properties of matter in a scanning electron microscope", adds Dr. Stefan Löffler, co-author of the study.

The complete study was published in Ultramicroscopy, opens an external URL in a new window.