Solid-state lasers: status and future [Invited]

In the past 50 years since Maiman's first demonstration of the ruby laser [Nature187, 493 (1960)], numerous types of laser ions and host materials have been developed with emission wavelengths from the ultraviolet to the mid-infrared spectral range. Despite the rapid progress in semiconductor laser technology, solid-state lasers still play an important role in many fields in science, industry, and daily life. In this paper we give a brief introduction into the fabrication techniques for laser crystals and the interplay between the host material and the laser ion. We review the current state of the art of some important solid-state laser concepts for continuous wave and pulsed operation modes. Finally, we present a selection of potential well-noted topics which may be important in future research and for the development of novel solid-state lasers.