Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.
DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.
In this paper, we present a novel Brillouin fiber-ring laser utilizing an unbalanced Mach-Zehnder interferometer (UMZI) as coupling device. The laser is pumped by a distributed-feedback laser diode and shows continuous-wave and single-frequency operation. Frequency-dependent transmission characteristics of the UMZI make it possible for the pump wave to pass through the laser-ring cavity with no resonance effect for stable pump operation, while the Brillouin laser signal still resonates in a high-finesse cavity. Single and multiple longitudinal mode operations are observed according to the relative location between longitudinal modes and Brillouin gain-curve center. A stable single-frequency operation is achieved using a simple stabilizing feedback loop based on dithering and autotracking techniques. Using this simple stabilizing feedback loop, the laser-intensity fluctuation is highly suppressed and remains below 4%. The Brillouin output converted from the pump power of 26.4 mW is about 3.18 mW, and the linewidth is measured to be below 1 kHz