Growth and characterization of TbAs films

We report on the molecular beam epitaxygrowth and characterization of TbAsfilms.In situreflection high energy electron diffraction andex situ high resolution X-ray diffraction, reciprocal space mapping, and both scanning andtransmission electron microscopy are used to confirm the completefilmgrowth and study thefilms' morphology. Spectrophotometry measurements provide the energy of optical transitions, revealing a red shift in optical band gap with increasing thickness. The Hall effect measurements show temperature insensitivecarrier concentrations, resistivities, and mobilities. Thecarrier concentration decreases and resistivity increases with increasingfilm thickness; mobility appears thickness independent. Thefilms' reflectivity, obtained via Fourier transform infrared spectroscopy, shows a possible Drude edge that differs from the trend of other lanthanide monopnictides. These measurements show that TbAs is a degeneratelydoped semiconductor with a combination of electronic andoptical properties that is dissimilar to other lanthanide monopnictides.

Source: Applied Physics Letters - November 15, 2016 Category: Physics Authors: Cory C. Bomberger, Bo E. Tew, Matthew R. Lewis and Joshua M. O. Zide Source Type: research