Self-sustained operation of a laser oscillating Mach?Zehnder interferometer

An experimental investigation was made of the operation of a laser oscillating Mach–Zehnder interferometer representing an optoelectronic self-oscillatory system with a delayed feedback loop. Single-sustained steady-state lasing was selected out of many possible ways of operating this interferometer. This type of operation is of practical importance, for example, when the interferometer is used as a sensor with a frequency output.