Tunable single frequency erbium doped optical fiber annular cavity laser with stable output wavelength and power

Abstract

A tunable single-frequency erbium-doped optical ring cavity laser with stable output wavelength and power comprises an erbium-doped optical laser, a first 1*2 3dB optical coupler, a second 2*2 3dB optical coupler, a third 2*2 3dB optical coupler, an optical fiber Fabry-Perot tunable filter and a polarization controller which are connected sequentially, wherein the optical fiber Fabry-Perot tunable filter, the polarization controller and the third 2*2 3dB optical coupler form a second main active ring, a 1*2 95:5 optical coupler and an optical gating filter are connected between the second 2*23dB optical coupler and the first 1*2 3dB optical coupler in series, thereby forming a first main active ring. The laser not only can guarantee continuous tuning in a wide range of wavelength, but can greatly improve stability of the output wavelength and power, thereby realizing stable output of single longitudinal modes.

Description

technical field [0001] The invention belongs to the technical field of optical fiber communication, and more specifically relates to a tunable single-frequency erbium-doped fiber ring cavity laser with stable output wavelength and power. Background technique [0002] Whether it is an optical wavelength division multiplexing or optical time division multiplexing system, the light source technology is one of the core technologies. The continuous operation of the erbium-doped fiber ring cavity laser has a simple structure, the lasing wavelength can be precisely predetermined, and broadband tuning and narrow linewidth output can be realized. , and compared with other lasers, it has many excellent characteristics such as high gain, low threshold, easy coupling with transmission fiber, etc. It can be widely used in optical communication, laser spectroscopy, fiber optic sensing and other fields, and has become a hot research topic today. Many practical applications require a single...

AI Technical Summary

Problems solved by technology

Many practical applications require a single longitudinal mode light source with stable intensity and continuous adjustment, and fiber Fabry-Perot tunable filters are usually used to adjust the output wavelength of fiber ring cavity lasers; however, due to the cavity of erbium-doped fiber ring cavity lasers The length generally reaches tens of meters. At the same time, because the bandwidth of the optical filter is several orders of magnitude larger than the longitudinal mode interval of the erbium-doped fiber laser, there are many longitudinal modes in the cavity that meet the conditions of the longitudinal mode.

At present, a double-ring structure is usually combined with two fiber Fabry-Perot tunable filters or a section of unpumped Erbium-doped fiber is used as a saturable absorber or a narrow linewidth fiber Bragg grating and several Mach-Zehnder mode filters Combined with other methods to obtain single longitudinal mode output, but these methods are still not enough to stabilize the lasing wavelength and power of the laser, and the structure is complex, it is not easy to realize in practical applications, which makes the tunable single longitudinal mode erbium-doped fiber ring cavity laser Practical application encountered great difficulties

Images