Multiwavelength Thulium-doped Fiber Laser Research Articles

Widely tunable multi-wavelength thulium-doped fiber laser based on nonlinear polarization rotation

A kind of widely tunable multi-wavelength thulium-doped fiber laser based on nonlinear polarization rotation (NPR) is achieved. Using a ring cavity, 1565 nm laser pump, a 3m long thulium doped fiber, and NPR effect is used as filter. By adjusting the fiber polarization controller, stable 1–5 wavelengths laser output is observed at room temperature, and the side mode suppression ratio is 40–60 dB. The measured results show that the wavelength shift is less than 0.2 nm within one hour and the output peak power fluctuation is less than ±3 dB. The wavelength spacing is about 6.75 nm and the tuning range is 33 nm. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1540–1543, 2016

Multi-Wavelength Thulium-Doped Fiber Laser Using a Fiber-Based Lyot Filter

A multi-wavelength thulium-doped fiber laser using a fiber-based Lyot filter is proposed in 2- $\mu \text{m}$ band for the first time. In the laser cavity, the fiber-based Lyot filter is used as the comblike wavelength selection component. By adjusting two polarization controllers, a stable multi-wavelength operation is obtained at room temperature, 17 output channels within 10-dB bandwidth from 1982 to 1998 nm are achieved. The flattened spectrum of multi-wavelength operation can obtained by using the 10% output coupling ratio. The different wavelength spacing of the fiber laser can be controlled by adjusting the polarization maintaining fiber lengths of the Lyot filters.

基于非线性偏振旋转效应的多波长掺铥锁模光纤激光器

基于非线性偏振旋转效应的多波长掺铥锁模光纤激光器

Widely tunable multiwavelength thulium-doped fiber laser using a fiber interferometer and a tunable spatial mode-beating filter

We propose and demonstrate a widely tunable multiwavelength thulium-doped fiber laser using a hybrid filter in order to expand the tuning range of a multiwavelength laser. The hybrid filter consists of an all-fiber interferometer and a tunable spatial mode-beating filter (SMBF). The operation principles of the interferometer and the tunable filter are analyzed. With a pump power of 200 mW, the number of wavelength can be tuned from one to nine by adjusting the polarization controller in the interferometer, and the multiwavelength laser can be tuned from 1896 to 1936 nm by adjusting the polarization controller in the SMBF. The wavelength spacing is 0.35 nm, and the linewidth of a single-wavelength is 0.03 nm. When pump power increases to 1 W, the spacing of dual-wavelength laser can be tuned from 6 to 36 nm.

Multiwavelength thulium-doped silica fiber laser incorporating an all-fiber phase modulator

A novel multiwavelength thulium-doped silica fiber laser incorporating an all-fiber phase modulator is first presented in 2μm band. In the laser cavity, a phase modulator with a modulation frequency is efficient and beneficial to overcome the mode competitions. A polarization maintaining fiber Sagnac loop mirror is used as the filter. Large number of lasing wavelengths can easily and conveniently obtained at a proper modulation frequency under room temperature. The fiber laser can achieve ten output channels within a 15dB bandwidth from 1982nm to 1998nm.

A multiwavelength thulium-doped silica fiber laser incorporating a highly nonlinear fiber

A multiwavelength Tm3+-doped silica fiber laser incorporating a highly nonlinear fiber is presented. In the laser cavity, a nonlinear polarization rotation (NPR) based fiber loop mirror is used to overcome the mode competition and a polarization-maintaining fiber Sagnac loop mirror is used as the filter. The 150 m highly nonlinear fiber can improve the NPR effect in the laser cavity, which can increase the number of output channels. By adjusting the polarization state of the polarization controllers properly, stable multiwavelength operation at the 2 μm spectrum can be obtained at room temperature. It can achieve 15 output channels within a 10 dB bandwidth from 1990 to 2007.5 nm. The channel spacing of the multiwavelength Tm3+-doped silica fiber laser is 1.22 nm. Moreover, the performance of the laser is investigated for different pump powers and fibers.

Stable multi-wavelength thulium-doped fiber laser based on all-fiber Mach–Zehnder interferometer

We propose and experimentally demonstrate a multi-wavelength thulium-doped fiber (TDF) laser based on all-fiber Mach-Zehnder interferometer (MZI) at 1.9 mm. Here a segment of 4 m single-mode TDF is pumped by 1568 nm fiber laser for 2 mm band optical gain. The MZI includes two cascaded 3 dB coupler. A segment of 3.5 m long un-pumped polarization-maintaining TDF and polarization controller (PC) are joined in the ring cavity to suppress the mode competition. Multi-wavelength lasers at 1.9 mm with wavelength number from one to four are obtained by adjusting the PC and the stability of output power of multi-wavelength fiber laser is analyzed.

A 1.97 μm multiwavelength thulium-doped silica fiber laser based on a nonlinear amplifier loop mirror

A 1.97 μm multiwavelength Tm-doped fiber laser based on a nonlinear amplifier loop mirror (NALM) has been experimentally demonstrated. The NALM with 500 m standard single mode fiber introduces intensity-dependent gain to alleviate mode competition caused by homogeneous gain broadening in Tm-doped fibers. At room temperature, up to 42 wavelengths with a wavelength spacing of 0.33 nm oscillate within a 10-dB bandwidth simultaneously. Repeat measurement of the laser spectrum shows the wavelength drift of a multiwavelength Tm-doped fiber laser is less than 0.05 nm in 40 min.