Abstract

Low-threshold lasers are interesting for a number of technological as well as fundamental aspects. Micrometric scale semiconductor lasers have brought an impressive progress in this direction. Recently, a single atom microlaser was also reported. In the first case, the mode volume is very small but the cavity Q low, and in the other exactly the opposite is the case. We report here on ultralow threshold laser action in a Neodynium doped silica microsphere which combines the advantages of these two systems, namely, extremely low mode volume and high Q.

© 1996 IEEE