Spectroscopy of new chromium/neodymium-doped oxide laser materials: garnets and aluminates

Applications to laser materials processing requires a novel solid state laser characterized by higher efficiency and larger output energy than the standard commercial materials. There is a revival of interest in the laser-type materials doped either by rare-earth ions (Nd3+, Er3+, Ho3+) or by metal-transition ions (Ni2+, Co2+, V2+, Cr3+, Ti3+). The spectral range of the emission is located in the near infrared and we have the possibility to obtain both a single-frequency laser with rare-earth centers and a tunable-frequency laser with metal-transition centers. In this paper we deal with: Nd3+-doped GGG-type garnets and Nd3+-doped lanthanum magnesium aluminate; Cr3+-doped GGG-type garnets and Cr3+-doped lanthanum magnesium aluminate; Cr3+/Nd3+-codoped GGG-type garnets.