Short-wavelength Tm-doped fiber laser with wave band of 1.6-1.7 microns

Abstract

The invention discloses a short-wavelength Tm-doped fiber laser with a wave band of 1.6-1.7 microns. The laser is characterized in that a pumping source emits pumping light in an Er-doped active fiber absorption band, and the Er-doped active fiber absorbs the pumping light; when the laser gain exceeds the loss of an Er-doped fiber laser resonant cavity formed by a first Er-doped fiber laser fiber grating and a second Er-doped fiber laser fiber grating which highly reflect a certain wavelength in the L-band, L-band laser near 1570nm is formed to oscillate in the resonant cavity; the Tm-doped active optical fiber absorbs 1570-nm laser and generates laser gain, short-wavelength laser with the wave band of 1.6-1.7 microns is formed under the action of a Tm-doped optical fiber laser resonant cavity formed by the Tm-doped optical fiber laser high-reflection optical fiber grating and the Tm-doped optical fiber laser output optical fiber grating, oscillates in the resonant cavity and is output through the Tm-doped optical fiber laser output optical fiber grating; and the Tm-doped active optical fiber is arranged in a resonant cavity of the Er-doped optical fiber laser.

Description

technical field

[0001] The invention relates to the field of fiber lasers, in particular to a short-wavelength Tm-doped fiber laser in the 1.6-1.7 μm band. Background technique

[0002] Tm (thulium)-doped fiber has a broad emission spectrum covering 1.6-2.1 μm, so fiber lasers using Tm-doped fiber as gain medium have extremely wide wavelength tuning potential. However, the current output wavelength of Tm-doped fiber lasers is mainly concentrated around the 1.9μm emission peak of Tm-doped fiber, and can be extended to 1.7-1.8μm and 2.0μm through certain wavelength selection measures. Reports are relatively rare. The reason is that on the one hand, the stimulated emission cross section of Tm ions at short wavelengths is significantly lower than that at 1.9 μm, which is similar to the situation at 2.0 μm at long wavelengths; The wavelength band is close to the absorption peak of Tm ions at 1.5-1.6 μm, and the stimulated absorption cross section is relatively large, which will ...

Examples

Embodiment 1

[0030] An embodiment of the present invention provides a short-wavelength Tm-doped fiber laser in the 1.6-1.7 μm band. The laser includes: a pump source 1, a pump coupling device 2, a first Er-doped fiber laser fiber grating 3, an Er-doped active Fiber 4, Tm-doped fiber laser high reflection fiber grating 5, Tm-doped active fiber 6, Tm-doped fiber laser output fiber grating 7, second Er-doped fiber laser fiber grating 8;

[0031]Among them, the pump source 1 is a fiber-coupled multimode semiconductor laser with a wavelength of 980 nm and a fiber core diameter of 100 μm; the pump coupling device 2 is a signal-pump combiner with a pump pigtail core diameter of 100 μm, and the pump source The fiber specifications of 1 match, and the signal fiber is a single-mode double-clad fiber; the first Er-doped fiber laser fiber grating 3 has a high reflectivity for the 1570nm wavelength corresponding to the Tm ion absorption peak in the Er ion L-band, and the reflectance is greater than 99 ...

Embodiment 2

[0035] In the above-mentioned embodiment 1, the pump gain fiber 4 can be an Er-doped fiber, or an Er / Yb co-doped fiber, as long as the gain at the 1.51-6 μm absorption band corresponding to the Tm-doped fiber 6 can be provided, the present invention implements Examples are not limited to this.

[0036] The pumping source 1 can be a multimode semiconductor laser, or a single transverse mode semiconductor laser or other types of lasers, and the pumping wavelength can be 980nm or 915nm and other wavelengths, as long as the corresponding Er-doped active fiber 4 (or The absorption band of the Er / Yb co-doped optical fiber) is enough, which is not limited in the embodiment of the present invention.

[0037] Correspondingly, if the pump source 1 is a single transverse mode pump source, the corresponding pump coupling device 2 is a wavelength division multiplexer (WDM) or other type of single-mode coupling device, which is not limited in the embodiment of the present invention .

technical field

[0001] The invention relates to the field of fiber lasers, in particular to a short-wavelength Tm-doped fiber laser in the 1.6-1.7 μm band. Background technique

[0002] Tm (thulium)-doped fiber has a broad emission spectrum covering 1.6-2.1 μm, so fiber lasers using Tm-doped fiber as gain medium have extremely wide wavelength tuning potential. However, the current output wavelength of Tm-doped fiber lasers is mainly concentrated around the 1.9μm emission peak of Tm-doped fiber, and can be extended to 1.7-1.8μm and 2.0μm through certain wavelength selection measures. Reports are relatively rare. The reason is that on the one hand, the stimulated emission cross section of Tm ions at short wavelengths is significantly lower than that at 1.9 μm, which is similar to the situation at 2.0 μm at long wavelengths; The wavelength band is close to the absorption peak of Tm ions at 1.5-1.6 μm, and the stimulated absorption cross section is relatively large, which will ...

Examples

Embodiment 1

[0030] An embodiment of the present invention provides a short-wavelength Tm-doped fiber laser in the 1.6-1.7 μm band. The laser includes: a pump source 1, a pump coupling device 2, a first Er-doped fiber laser fiber grating 3, an Er-doped active Fiber 4, Tm-doped fiber laser high reflection fiber grating 5, Tm-doped active fiber 6, Tm-doped fiber laser output fiber grating 7, second Er-doped fiber laser fiber grating 8;

[0031]Among them, the pump source 1 is a fiber-coupled multimode semiconductor laser with a wavelength of 980 nm and a fiber core diameter of 100 μm; the pump coupling device 2 is a signal-pump combiner with a pump pigtail core diameter of 100 μm, and the pump source The fiber specifications of 1 match, and the signal fiber is a single-mode double-clad fiber; the first Er-doped fiber laser fiber grating 3 has a high reflectivity for the 1570nm wavelength corresponding to the Tm ion absorption peak in the Er ion L-band, and the reflectance is greater than 99 ...

Embodiment 2

[0035] In the above-mentioned embodiment 1, the pump gain fiber 4 can be an Er-doped fiber, or an Er / Yb co-doped fiber, as long as the gain at the 1.51-6 μm absorption band corresponding to the Tm-doped fiber 6 can be provided, the present invention implements Examples are not limited to this.

[0036] The pumping source 1 can be a multimode semiconductor laser, or a single transverse mode semiconductor laser or other types of lasers, and the pumping wavelength can be 980nm or 915nm and other wavelengths, as long as the corresponding Er-doped active fiber 4 (or The absorption band of the Er / Yb co-doped optical fiber) is enough, which is not limited in the embodiment of the present invention.

[0037] Correspondingly, if the pump source 1 is a single transverse mode pump source, the corresponding pump coupling device 2 is a wavelength division multiplexer (WDM) or other type of single-mode coupling device, which is not limited in the embodiment of the present invention .

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