Articles you may be interested in Photon-induced positron annihilation lifetime spectroscopy using ultrashort laser-Compton-scattered gamma-ray pulses Rev. Sci. Instrum. 84, 053305 (2013); 10.1063/1.4807701 Strong quantum size effects in transition metal silicide ultrathin films: Critical role of Fermi surface nesting Positron annihilation and Compton scattering are important probes of the Fermi surface. Relying on conservation of energy and momentum, being bulk sensitive and not limited by short electronic mean-free-paths, they can provide unique information in circumstances when other methods fail. Using a variety of examples, their contribution to knowledge about the electronic structure of a wide range of materials is demonstrated. V C 2014 AIP Publishing LLC.