Abstract

Semiconductor ring-type lasers that do not use cleaved-facet mirrors^1,2 are promising for integrated photonic logic devices. Realization of a square-shaped laser when using straight waveguides and total reflection mirrors (hereafter an orbiter laser) would be advantageous, not only for their low-threshold operation potential but also for their novel functional capabilities exploiting clockwise and counterclockwise traveling wave oscillation. In this paper we demonstrate unidirectional oscillation of square orbiter lasers in semiconductor ring lasers for the first time. The orbiter lasers are also found to exhibit a unique optical bistability.

© 1991 Optical Society of America