CN110596814A

CN110596814A - Optical fiber corrosion groove type echo wall resonator based on microspheres

Info

Publication number: CN110596814A
Application number: CN201810600356.7A
Authority: CN
Inventors: 王东宁; 白雪倩
Original assignee: China Jiliang University
Current assignee: China Jiliang University
Priority date: 2018-06-12
Filing date: 2018-06-12
Publication date: 2019-12-20
Anticipated expiration: 2038-06-12
Also published as: CN110596814B

Abstract

The invention provides a microsphere-based optical fiber end-face type echo wall resonator, which comprises a broadband light source, a circulator, an echo wall structure and a spectrum analyzer. The echo wall structure is composed of a single mode fiber, a coreless fiber, a multimode fiber, ultraviolet glue and microspheres. The method is characterized in that: and finally, adhering a microsphere at a proper position at the bottom of the groove to form an echo wall structure. The light from the broadband light source is received by the circulator and transmitted to the echo wall structure, and the echo wall structure returns the light to the circulator and transmits the light to the optical spectrum analyzer through the circulator to form the echo wall mode resonator. The invention has the advantages of compact structure, simple manufacture, high and stable quality factor, insensitive temperature influence and the like, and can be used for optical lasers, sensors, photoelectron information, biological detectors and the like.

Description

Optical fiber corrosion groove type echo wall resonator based on microspheres

Technical Field

The invention provides an optical fiber corrosion groove type echo wall resonator based on microspheres, and belongs to the technical field of optical fiber devices.

Background

When light travels along the edges of a cavity by total internal reflection, a standing wave may form if the light path around the cavity is an integer multiple of the wavelength. This standing wave mode is commonly referred to as a whispering gallery mode, and the resulting cavity is referred to as a whispering gallery mode resonator. The whispering gallery mode resonator may be formed of different shapes, such as microdisk, microsphere, etc. Among them, the mode of exciting the whispering gallery by the microsphere structure is most widely used. Whispering gallery mode resonators have both the advantages of high quality factor and low mode volume, making them useful in many applications such as high sensitivity sensors, narrow band filters, micro lasers and modulators.

There are many different methods for exciting whispering gallery modes, such as by prism, pedestal waveguide, side polished fiber, angle polished fiber tip, and fiber taper. Light can be coupled into the microspheres by evanescent waves at the inner surface of the phase-matched prism. The prism coupling method is efficient and flexible, but has large volume and is inconvenient in practical application. The on-chip base structure can efficiently couple light into the microsphere structure, but the base waveguide structure is complex and requires high fabrication accuracy. Fiber pigtail couplers are preferred from an application point of view, and methods of side polishing the fiber and angle polishing the fiber tip have been used to excite high quality factor microsphere resonators. However, the optical coupling efficiency of these two methods is not high. The coupling efficiency of the side polished optical coupler is much higher for large diameter microspheres of about 1mm than for small diameter resonators. Tapers below 2 μm are the most efficient coupling in these methods, but the taper structure is fragile and is greatly affected by environmental changes.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides the optical fiber end face groove type echo wall resonator based on the microspheres, and the optical fiber end face groove type echo wall resonator has the advantages of compact structure, simplicity in manufacturing, high and stable quality factors and the like.

The technical scheme adopted by the invention for solving the technical problem is as follows: a microsphere-based fiber corrosion groove echo wall resonator comprises a broadband light source, a circulator, an echo wall structure and a spectrum analyzer. The echo wall structure is composed of single mode fiber, coreless fiber, multimode fiber, ultraviolet glue and microsphere. The method is characterized in that: and finally, adhering a microsphere at a proper position at the bottom of the groove to form an echo wall structure.

The diameter of the fiber core of the single-mode fiber and the diameter of the fiber are respectively 8 mu m and 125 mu m, and the refractive index of the fiber core is 1.4682; the diameter and the refractive index of the coreless fiber are 125 mu m and 1.4446 respectively; the core diameter and the fiber diameter of the multimode fiber are respectively 62.5 mu m and 125 mu m, and the core refractive index is 1.4682.

The material and refractive index of the microsphere are respectively barium titanate and 1.9.

Compared with the prior art, the invention has the beneficial effects that.

1. The whispering gallery mode resonator is prepared by using low-price common single-mode optical fibers, coreless optical fibers, multimode optical fibers, ultraviolet glue and microspheres, and has the advantages of low cost and simple manufacture.

2. The whispering gallery mode resonator has the advantages of small size, good structural stability and high quality factor.

3. The whispering gallery mode resonator has low temperature sensitivity and is insensitive to ambient temperature changes when used as a sensor.

Drawings

In order to more clearly illustrate the embodiments or technical solutions of the present invention, the present invention is further described below with reference to the accompanying drawings and embodiments.

FIG. 1 is a schematic diagram of an application system of the present invention.

Fig. 2 is a schematic diagram of the echo wall structure of the present invention.

In the figure, 1, a broadband light source, 2, a circulator, 3, a whispering gallery structure, 4, a spectrum analyzer, 5, a single-mode fiber, 5a, a single-mode fiber core, 5b, a single-mode fiber cladding, 6, a coreless fiber, 7, a multimode fiber, 7a, a multimode fiber core, 7b, a multimode fiber cladding, 8, a groove, 9, ultraviolet glue, 10 and microspheres.

Detailed Description

The invention is further described below with reference to the accompanying drawings and examples:

fig. 1 is a schematic diagram of an application system of the present invention, which includes a broadband light source 1, a circulator 2, an echo wall structure 3, and a spectrum analyzer 4. The connection mode is as follows: the circulator 2 has three interface ends, which are respectively: light source inlet end, light source outlet end, feedback end. The inlet end is connected with a broadband light source 1, the outlet end is connected with a connecting echo wall structure 3, and the feedback end is connected with a spectrum analyzer 4.

Fig. 2 is a schematic structural diagram of the echo wall structure 3 of the present invention, and the echo wall structure 3 includes a single-mode fiber 5, a coreless fiber 6, a multimode fiber 7, a groove 8, an ultraviolet glue 9, and microspheres 10. The single-mode fiber 5 comprises a single-mode fiber core 5a and a single-mode fiber cladding 5 b; the multimode optical fiber 7 includes a multimode optical fiber core 7a and a multimode optical fiber cladding 7b.

The manufacturing method and the steps of the echo wall structure are as follows: the first step is as follows: sequentially welding the single-mode optical fiber 5 with the coreless optical fiber 6 and the multi-mode optical fiber 7 by using a welding machine; the second step is that: putting the other end of the multimode optical fiber 7 into hydrofluoric acid, and corroding for a certain time to form a groove 8; the third step: coating a proper amount of ultraviolet glue 9 at the bottom of the groove of the multimode optical fiber 7 to stick the microsphere 10 so as to form a whispering gallery mode; the fourth step: ultraviolet glue 9 is cured by an ultraviolet lamp, so that the whole structure is more stable.

With reference to fig. 1 and 2, a specific working principle is described: the echo wall structure 3 is a coupling surface formed by an arc surface of a multimode optical fiber 7 and a spherical surface of a microsphere 10, emitted by a broadband light source 1, and the emitted light reaches the echo wall structure 3 through a circulator 2, the light beam is firstly transmitted to a coreless optical fiber 6 through a single-mode optical fiber core 5a in the echo wall structure 3 to be scattered, then transmitted to the multimode optical fiber core 7a to be transmitted to have light of various modes for propagation, and is coupled to the microsphere 10 along a tangent line at the contact surface of the multimode optical fiber 7 and the microsphere 10, after one circle of transmission is carried out on the surface of the microsphere 8, the light beam is coupled back to the multimode optical fiber core 7a along the other direction of the tangent line of the contact surface, and then transmitted back to the single-mode optical fiber core 5a through the coreless optical fiber.

The above-mentioned embodiments, which further illustrate the objects, technical solutions and advantages of the present invention, should be understood that the above-mentioned embodiments are only examples of the present invention, and should not be construed as limiting the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides an optic fibre terminal surface recess formula echo wall syntonizer based on microballon, includes broadband light source, circulator, echo wall structure, spectral analysis appearance, and its connected mode is: broadband light source is connected to the circulator input, and the spectral analysis appearance is connected to circulator feedback end, and the circulator output is connected echo wall structure, its characterized in that: the echo wall structure is composed of a single mode fiber, a coreless fiber, a multimode fiber, ultraviolet glue and microspheres; and finally, adhering a microsphere at a proper position at the bottom of the groove to form an echo wall structure.

2. The microsphere-based optical fiber end face groove-type echo wall resonator according to claim 1, wherein: the diameter of the fiber core of the single-mode fiber and the diameter of the fiber are respectively 8 mu m and 125 mu m, and the refractive index of the fiber core is 1.4682; the diameter and the refractive index of the coreless fiber are 125 mu m and 1.4446 respectively; the core diameter and the fiber diameter of the multimode fiber are respectively 62.5 mu m and 125 mu m, and the core refractive index is 1.4682.

3. The microsphere-based optical fiber end face groove-type echo wall resonator according to claim 1, wherein: the material of the microsphere is barium titanate, and the refractive index is 1.9.