Upconversion for White Light Generation by a Single Compound

Abstract
A new multiphoton upconversion process for rare earth oxide powders is reported, using infrared laser diodes. In vacuum, multiphoton excitation produces intense upconversion emission in the visible spectral range, and Tm(2)O(3) or Yb(2)O(3) achieves pure white upconversion using 808 or 975 nm excitation, respectively.