In this letter, we demonstrate the operation of optical bistability in a widely tunable semiconductor fiber ring laser, using a semiconductor optical amplifier (SOA). The laser can be operated in two bistable states: the spectrum of the first state has one main lasing peak with very narrow linewidth, and the second state has simultaneous oscillation of two main peaks at different wavelengths. The two bistable states can be switched to each other using either electrical or optical methods. We further explain the bistable operation using the theory of two-mode competition through gain saturation in SOA.
- optical bistability
- optical logic devices
- ring lasers
- semiconductor optical amplifiers
- wavelength-division multiplexing