CN203166299U - Miniature tunable wavelength single-mode fiber laser - Google Patents

Abstract

A wavelength tunable miniature single-mode fiber laser, comprising a first optical wavelength division multiplexer and a second optical wavelength division multiplexer respectively connected to the first semiconductor pump laser and the second semiconductor pump laser, and the first optical wavelength division multiplexer The first output port connected to the multiplexer, the second output port connected to the second optical wavelength division multiplexer, and a nested double-ring micro-resonator arranged on the substrate, the nested double-ring micro-resonator consists of Active micro-nano optical fibers are knotted into two inner rings and outer rings with different diameters. The ring structure is connected to the first cone of the common end of the first optical wavelength division multiplexer and the second optical wavelength division multiplexer Shaped optical fiber is coupled with the second tapered optical fiber, and the common end of the second optical wavelength division multiplexer is provided with a piezoelectric ceramic controlled by the signal generator. The utility model adopts a nested double-ring micro-resonator cavity, and by changing the The parameters of the coupling area with the resonant cavity realize different wavelength tuning outputs.

Description

A wavelength-tunable miniature single-mode fiber laser

technical field

The utility model relates to a light source used in the fields of optical fiber sensing, optical integration and coherent detection, and is a wavelength-tunable miniature single-mode laser based on micro-nano optical fiber.

Background technique

The micro-nano single-mode fiber laser with tunable wavelength is to fuse and pull the diameter of the active fiber to the order of micron or nanometer size (that is, micro-nano fiber), and then use micro-operations to precisely control it to form a resonant cavity with a ring structure. Optical resonators are only a few hundred micrometers in diameter and a few millimeters in length. Compared with the traditional semiconductor-etched micro-optical cavity, it has the following advantages: 1. The micro-fiber laser provides gain through a section of doped micro-nano fiber, and the optical resonator composed of the gain fiber has multiple functions of filtering and frequency selection, and the structure is compact ; 2. The micro fiber laser uses tapered fiber coupling output. Due to the unique flexibility of the fiber, parameters such as the position of the coupling area, the coupling length and the coupling angle can be arbitrarily designed; 3. The micro fiber laser is simple in structure, easy to operate, and the cost is very low , to meet the application requirements of different fields; 4. The output wavelength of the miniature fiber laser can be tuned.

At present, there are some insurmountable shortcomings in the micro-laser obtained by traditional etching: on the one hand, once the micro-laser obtained by the etching method is formed, its structure cannot be changed, which is inconvenient for subsequent debugging and operation; The method is expensive and requires complex production equipment and sophisticated testing instruments to strictly control its products. Therefore, for chip-level applications, there is an urgent need for a micro-laser with low cost, easy operation, and stable performance.

At present, there have been reports on the use of micro-nano fibers to make micro-lasers. The utility model "micro-fiber ring junction laser" made by Tong Limin of Zhejiang University uses doped fibers to make a single-ring structure, but this structure cannot realize the tuning of the laser wavelength, and it is not easy to realize. Single mode laser output. Li Qizhen of Huazhong University of Science and Technology and other utility models "micro-nano optical fiber filter, optical fiber laser, optical fiber sensing equipment and manufacturing method", proposed a "8"-shaped laser cavity, but this structure did not realize the laser wavelength. tuning output.

Utility model content

The purpose of the utility model is to solve the problems in the prior art, and propose a novel wavelength tunable miniature single-mode fiber laser.

On the premise of not using fiber gratings, F-P filters and other components, the utility model proposes to adopt a nested double-ring micro-resonator structure, and the output laser must meet the resonance conditions of each ring at the same time, and the single-mode laser output is realized simply and conveniently. In addition, the output fiber cone and the nested double-ring micro-resonator coupling area have selectivity to different wavelength lasers, and the parameters (length, angle, etc.) of the coupling area can be precisely adjusted through piezoelectric ceramics to realize the output of different wavelength lasers.

The purpose of this utility model is achieved through the following technical solutions:

A wavelength tunable miniature single-mode fiber laser, comprising a first optical wavelength division multiplexer and a second optical wavelength division multiplexer respectively connected to the first semiconductor pump laser and the second semiconductor pump laser, and the first optical wavelength division multiplexer The first output port connected to the multiplexer, the second output port connected to the second optical wavelength division multiplexer, and a nested double-ring micro-resonator arranged on the substrate, the nested double-ring micro-resonator consists of Active micro-nano optical fibers are knotted into two inner rings and outer rings with different diameters. The ring structure is connected to the first cone of the common end of the first optical wavelength division multiplexer and the second optical wavelength division multiplexer The optical fiber is coupled with the second tapered optical fiber, and the common end of the second optical wavelength division multiplexer is provided with a piezoelectric ceramic controlled by a signal generator.

Further, the active micro-nano fiber is a light-emitting fiber doped with rare earth ions or transition metal ions.

Further, the pigtails of the first tapered optical fiber and the second tapered optical fiber have a length of 5 μm to 5 mm and a diameter of 0.8 to 5 μm, and match the diameter of the active micro-nano fiber used in the nested double-ring micro-resonator .

The active optical fiber with a diameter of 0.8~5μm is knotted into a nested double-ring micro-resonator cavity through micro-operation, and the tapered optical fiber is used as the input end of the semiconductor pump laser and the laser output end, and its diameter matches the diameter of the active micro-nano optical fiber. The semiconductor pump laser is turned on, the two are coupled by evanescent waves, the pump light is injected into the resonator, and the single-mode laser formed in the resonator is output. By adjusting the coupling length and coupling angle between the tapered fiber and the resonator, Realize the tuning of the laser wavelength.

Compared with the prior art, the utility model has the following main advantages:

The utility model adopts the active cavity structure directly as a filter, and does not need to be connected with a high-cost filter.

 本实用新型采用特殊的嵌套双环微型谐振腔进行模式的选择，只有同时满足两个环形腔结构的纵模才能起振，这种简单有效的选模方式更容易实现单纵模激光的振荡输出。

The utility model adopts a special nested double-ring micro-resonator cavity for mode selection, and only the longitudinal modes satisfying the structure of two ring cavities at the same time can start to vibrate. This simple and effective mode selection method is easier to realize the oscillation output of a single longitudinal mode laser .

The utility model adopts the coupling mode of the tapered optical fiber and the miniature optical fiber resonant cavity to inject the pumping light and output the signal laser. This flexible structure is an important prerequisite for wavelength tuning. parameters (coupling length, angle, etc.) to achieve different wavelength tuning output.

Description of drawings

Fig. 1 is a structural schematic diagram of the optical path device described in the utility model;

Fig. 2 is the structure schematic diagram of miniature double collar resonant cavity and optical fiber taper described in the utility model;

Fig. 3 is a spectrum diagram of tuned wavelengths in the embodiment of the utility model.

Detailed ways

The utility model will be further described and explained below in conjunction with specific implementation examples and accompanying drawings, but is not limited to this implementation mode.

As shown in Figure 1, the wavelength tunable miniature single-frequency fiber laser consists of a double-ring microresonator 1, a substrate 2, a first optical wavelength division multiplexer 3, a second optical wavelength division multiplexer 4, and a first semiconductor pump A laser 5 , a second semiconductor pump laser 6 , a piezoelectric ceramic 9 , a signal generator 10 , and a first output port 7 and a second output port 8 are formed. In this embodiment, the pumping wavelength of the first semiconductor pumping laser 5 and the second semiconductor pumping laser 6 is 976nm, the output power is adjustable, and the output pigtail is a single-mode fiber. The first semiconductor pump laser 5 and the second semiconductor pump laser 6 respectively provide the first optical wavelength division multiplexer 3 and the second optical wavelength division multiplexer 4 to provide pumping energy (positive to, reverse). The common end of the first optical wavelength division multiplexer 3 is tapered and connected to the nested double-ring micro-resonator cavity 1 . The common end of the second optical wavelength division multiplexer 4 is tapered and connected to the double-ring micro-resonator cavity 1, and the piezoelectric ceramic 9 is loaded on the common end of the second optical wavelength division multiplexer 4 and controlled by a signal generator 10 The piezoelectric ceramic parameters. Finally, the laser light is output through the first output port 7 and the second output port 8 .

2cm。 As shown in FIG. 2 , the double-ring micro-resonator cavity 1 used in the present invention is composed of an outer ring 11 , an inner ring 12 and a substrate 2 . The double-ring micro-resonator used in this embodiment is drawn from Erbium-Ytterbium co-doped phosphate fiber, and its diameter is 1.88 μm, and the diameters of the rings are 206 μm and 351 μm, respectively. The substrate 2 used in this embodiment is a magnesium fluoride substrate with a refractive index of 1.38 and a size of 1

2cm.

As shown in FIG. 2 , the optical fiber tapers used in the present invention are respectively drawn from the common ends of the first tapered optical fiber 31 and the second tapered optical fiber 41 . The diameter of the cone tail is 1.9 μm, and the length is 30 μm. This structure can effectively inject the pump light from the traditional core-clad interface into the double-ring miniature fiber resonator. Damage to devices caused by reflected light.

As shown in Figure 3, the laser wavelength tunable spectrum output by the embodiment of the utility model is shown in the figure as two wavelengths with a spacing of 1.2nm. More tunable wavelengths can be obtained by finely adjusting piezoelectric ceramics, which are not shown here. List them all.

The active micro-nano optical fiber in the utility model is not only applicable to the erbium-ytterbium co-doped phosphate optical fiber, but also applicable to all active doped optical fibers. The substrate in the utility model is not only suitable for the magnesium fluoride substrate, but also suitable for various structures with a refractive index lower than 1.4 prepared by the airgel method. As mentioned above, the utility model can be better realized, and the above-mentioned embodiments are only preferred embodiments of the utility model, and are not intended to limit the implementation scope thereof.

Claims (3)

1. A wavelength tunable miniature single-mode fiber laser, comprising the first optical wavelength division multiplexer (3) and the first semiconductor pump laser (5) connected to the second semiconductor pump laser (6) respectively Two optical wavelength division multiplexers (4), a first output port (7) connected to the first optical wavelength division multiplexer (3), a second output port connected to the second optical wavelength division multiplexer (4) (8), characterized in that it also includes a nested double-ring micro-resonator (1) arranged on the substrate (2), and the nested double-ring micro-resonator (1) is two knotted active micro-nano optical fibers Consisting of inner rings (12) and outer rings (11) with different diameters, the nested double-ring micro-resonator (1) is respectively connected with the first optical wavelength division multiplexer (3) and the second optical wavelength division multiplexer ( 4) The first tapered optical fiber (31) at the common end is coupled with the second tapered optical fiber (41), and the common end of the second optical wavelength division multiplexer (4) is provided with a signal generator (10) controlled Piezoelectric ceramics (9). 2. The wavelength-tunable miniature single-mode fiber laser according to claim 1, wherein the active micro-nano fiber is a light-emitting fiber doped with rare earth ions or transition metal ions. 3. wavelength tunable miniature single-mode fiber laser according to claim 1, is characterized in that, the length of the tail fiber of described first tapered optical fiber (31) and the second tapered optical fiber (41) is 5 μm～5mm, diameter The diameter is 0.8-5 μm, and matches the diameter of the active micro-nano optical fiber used in the nested double-ring micro-resonator cavity (1).

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