Infrared and visible laser transitions in erbium-doped crystals

Abstract

Due to the peculiar energy level scheme of Er3+, with many energetic resonances, Er-doped crystals can generate laser radiations in various wavelength domains: at 3 µm with applications in medicine and biology, at 1.5 μm (for telecommunications) and in visible (green) with potential applications in medicine. Low concentrated Er-doped crystals are suitable for 1.5 μm and green (upconversion pumped) lasers while high concentrated ones - for 3 μm emission. In this paper we discuss the possibilities and the limits of the lasers based on erbium-doped crystals using rate equations models.