Photon cutting with efficiencies up to 400% is demonstrated in Er x Y 2− x Si 2 O 7 films grown on Si and its concentration dependence is analyzed. The cutting is the result of cross-energy-transfer processes occurring within a single rare earth (Er 3+) acting as both sensitizer and activator. Similarities with upconversion are revealed and possible applications in solar cells are discussed.
American Physical Society
15 Jan 2010
Volume: 81 Issue: 4 Pages: 041411
Physical Review B