Silicon optical integrated Bragg grating assembly and optical module

Abstract

The invention discloses a silicon optical integrated Bragg grating assembly and an optical module, the silicon optical integrated Bragg grating assembly comprises a silicon optical chip, the silicon optical chip is provided with a planar waveguide grating, a Bragg grating and a micro circulator, the planar waveguide grating comprises at least one optical waveguide input channel and a plurality of first optical waveguide output channels, each first optical waveguide output channel is correspondingly connected with one micro-circulator, each micro-circulator comprises two second optical waveguide output channels, and at least one second optical waveguide output channel is provided with the Bragg grating. The antenna has the advantages of being small in size, high in isolation degree and high in anti-interference capacity.

Description

Technical Field

[0001] The invention relates to a grating component, belonging to the technical field of optical modules, and in particular to a silicon optical integrated Bragg grating component and an optical module. Background Art

[0002] With the sharp increase in data demand for communication networks and the rapid development of technology, the transmission rate of optical communication networks continues to increase. Against this background, research on silicon photonic integration technology has received increasing attention. Silicon-based photonic devices have many advantages, including compatibility with complementary metal oxide semiconductor (CMOS) processes, small size, transparency in the communication band, and radiation resistance. At the same time, it also has the advantages of large bandwidth, low latency, low energy consumption, and low crosstalk. Emerging information technologies such as optical communication, optical interconnection, and optical sensing based on silicon photonic integration show a development trend of building new information hardware and are becoming an important foundation for the next generation of information systems and networks.

[0003] In optical communication systems, circulators and wavelength division multiplexers are key components. However, traditional circulators have some limitations. They usually use the magneto-optical effect and are composed of birefringent crystals and Faraday rotators. They have complex structures and large volumes, making them difficult to use in miniaturized systems. Similarly, existing wavelength division multiplexing components also face problems such as single function, large volume, low isolation between wavelength channels, and weak anti-interference ability.

[0004] In view of the above situation, developing a grating component with small size, high isolation and strong anti-interference ability has become an urgent need in the current optical communication field. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a silicon photonic integrated Bragg grating component and an optical module in view of the technical defects existing in the prior art. The component is based on silicon photonic integrated technology, utilizes the characteristics of parallel waveguide grating light splitting and Bragg grating wave splitting, integrates a planar waveguide grating and a Bragg grating on a silicon-based chip, and integrates an all-optical passive circulator on the silicon-based chip through the thermo-optical effect of silicon, connects the planar waveguide grating and the Bragg grating through the circulator, and forms a new silicon photonic integrated Bragg grating optical component to achieve the purpose of wavelength division. The new wavelength division component has a small size, high isolation, strong anti-interference ability, and flexible bandwidth layout.

[0006] The technical solution adopted by the present invention to solve its technical problem is: the present invention discloses a silicon photonic integrated Bragg grating component, including a silicon photonic chip, on which a planar waveguide grating, a Bragg grating and a microcirculator are arranged, the planar waveguide grating includes at least one optical waveguide input channel and multiple first optical waveguide output channels, each first optical waveguide output channel is correspondingly connected to a microcirculator, and each microcirculator includes two second optical waveguide output channels and at least one of the second optical waveguide output channels is provided with the Bragg grating.

[0007] In a preferred embodiment of the present invention, the planar waveguide grating includes one optical waveguide input channel and four first optical waveguide output channels.

[0008] In a preferred embodiment of the present invention, the second optical waveguide output channels are arranged in parallel and spaced apart.

[0009] In a preferred embodiment of the present invention, the planar waveguide grating, the Bragg grating and the microcirculator are etched on the silicon photonic chip by femtosecond laser.

[0010] In a preferred embodiment of the present invention, the microcirculator includes a P1 port, a P2 port and a P3 port, the P1 port is connected to the first optical waveguide output channel, the P2 port is connected to the second optical waveguide output channel and the Bragg grating, and the P3 port is connected to the second optical waveguide output channel.

[0011] In a preferred embodiment of the present invention, an optical signal is input from the P1 port and output from the P2 port; an optical signal input from the P2 port can only be output from the P3 port.

[0012] In a preferred embodiment of the present invention, a cover plate is provided on the silicon photonic chip.

[0013] The invention also discloses an optical module, comprising a silicon optical integrated Bragg grating component.

[0014] In a preferred embodiment of the present invention, it comprises a base plate, on which a single-fiber optical fiber array, a silicon optical integrated Bragg grating component and an arrayed hyperbolic silicon lens are arranged in sequence.

[0015] In a preferred embodiment of the present invention, the single-fiber optical fiber array comprises a bottom plate with an optical fiber positioning groove, a flat cover plate arranged on the bottom plate, and a tail end protective glue.

[0016] The beneficial effects of the present invention are as follows: the present invention discloses a silicon-based integrated wavelength division component, which divides the signal into independent wavelengths by directly etching a Bragg grating on the silicon substrate, and then etches a circulator optical path through the thermo-optical effect of the silicon chip, which is linked with the Bragg grating to form a silicon-based chip component. The fiber Bragg grating of the present invention is made by depositing and etching refractive index materials of different periods on a path. When the optical signal passes through the Bragg grating, the optical wavelength that meets the Bragg condition is reflected after passing through the grating surface, and the wavelength that does not meet the condition continues to be transmitted, thereby separating the wavelengths. The optical components manufactured using silicon photonic chip integration technology are smaller in size, and optical signals are coupled with the transmitting and receiving components at the input and output ends, which makes optical signal coupling more convenient. The integrated components can be used on a large scale for optical module data transmission and long-distance backbone communication network transmission through flexible spatial layout;

[0017] The present invention has made significant breakthroughs in integration and miniaturization. By integrating the planar waveguide grating, Bragg grating and microcirculator on the same silicon photonic chip, the size of the device is greatly reduced, overcoming the shortcomings of the traditional circulator, which has a complex structure and large size. This highly integrated design not only makes the device more compact, but also greatly improves its flexibility and applicability in various application scenarios.

[0018] The silicon photonic chip used in the present invention integrates an all-optical microcirculator to ensure that light can only be transmitted in a directional direction. The input optical signal can be directly coupled with the silicon photonic integrated chip through the optical fiber array, eliminating the traditional Faraday isolator. Traditional optical path signal transmission needs to be coupled with the isolator through the optical fiber array and then coupled with the wavelength division component. This integrated design improves the coupling efficiency in the production process, greatly improves the large-scale production capacity, and reduces material and manufacturing costs.

[0019] The present invention has achieved a qualitative leap in functionality and performance. The integration of multifunctional components overcomes the limitation of the single function of existing wavelength division components and realizes multifunctional integration. In particular, the separate loop design of the Bragg grating makes the modulation of different wavelengths more flexible, while significantly improving the isolation between channels and enhancing the anti-interference ability of the system. The special port design (P1, P2, P3) of the microcirculator realizes the directional transmission of optical signals, further improving the efficiency and controllability of signal transmission.

[0020] The present invention uses femtosecond laser etching technology to make various components on the silicon photonic chip, ensuring high precision and good consistency. The design of the silicon photonic integrated chip makes it easier to couple the device with other optical elements, greatly simplifying the system integration process. In addition, the cover plate set on the silicon photonic chip improves the durability and stability of the device.

[0021] The multi-output design (e.g., 1 input 4 outputs) of the planar waveguide grating disclosed in the present invention allows the system to be expanded as needed. As an independent optical module, it can be easily integrated with other components (e.g., single-fiber optical fiber array, arrayed hyperbolic silicon lens, etc.), further improving the applicability of the system. It is particularly worth mentioning that the precision design of the single-fiber optical fiber array (including optical fiber positioning grooves, flat cover plates, and tail end protective glue) ensures precise alignment between the optical fiber and the chip, improving the transmission efficiency of the optical signal.

[0022] The silicon photonic integrated Bragg grating component disclosed in the present invention not only overcomes many shortcomings of traditional optical components, but also achieves innovation in many aspects such as integration, functionality, performance, manufacturing process and ease of use. It provides a new solution for the miniaturization and high-performance development of optical communication systems and is expected to play an important role in future optical communication technologies. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0024] Figure 1 A schematic diagram of an optical module of the present invention;

[0025] Figure 2 A top view of the optical module of the present invention;

[0026] Figure 3 A schematic diagram of the present invention;

[0027] Figure 4 Schematic diagram of two plane wave superposition models of the present invention;

[0028] Figure 5 Schematic diagram of the working principle of the Bragg grating structure of the present invention. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0030] The present invention discloses a silicon photonic integrated Bragg grating component and an optical module. Specifically, the components utilize the characteristics of parallel waveguide grating light splitting and Bragg grating wave splitting to integrate a planar waveguide grating and a Bragg grating on a silicon-based chip, and integrate an all-optical passive circulator on the silicon-based chip through the thermo-optical effect of silicon, connect the planar waveguide grating and the Bragg grating through the circulator, and form a new silicon photonic integrated Bragg grating optical component to achieve the purpose of wavelength division. The new wavelength division component has a small size, high isolation, strong anti-interference ability, and flexible bandwidth layout.

[0031] Example 1

[0032] This embodiment provides a silicon photonic integrated Bragg grating component, the core of which is a silicon photonic chip 4. The silicon photonic chip 4 not only integrates multiple key optical components, but also realizes efficient optical signal processing and transmission through structural design.

[0033] The silicon photonic chip 4 integrates three main optical functional units: a planar waveguide grating 4-1, a microcirculator 4-2 and a Bragg grating 4-3. This highly integrated design greatly reduces the volume of the entire component while improving the efficiency of optical signal processing.

[0034] The planar waveguide grating 4-1 is the entrance of the whole system, which includes one optical waveguide input channel and four first optical waveguide output channels. This 1-input 4-output design provides great flexibility for the system and can process multiple optical signals at the same time. Each first optical waveguide output channel is connected to a microcirculator 4-2, forming four independent signal processing units.

[0035] The microcirculator 4-2 is a key element in this design. Each microcirculator contains three ports: P1, P2 and P3. The P1 port is connected to the first optical waveguide output channel and serves as the input port of the signal; the P2 port is connected to the second optical waveguide output channel and the Bragg grating 4-3, which can be used as an output port and can also receive feedback signals from the Bragg grating; the P3 port is connected to another second optical waveguide output channel and is mainly used to output the signal input from the P2 port. This design realizes the directional transmission of optical signals: the signal input from the P1 port can be output from the P2 port, while the signal input from the P2 port can only be output from the P3 port.

[0036] The Bragg grating 4-3 is another important functional unit, which is set on at least one second optical waveguide output channel. The function of the Bragg grating is to reflect the optical signal of a specific wavelength, which allows us to accurately control and adjust the optical signals of different wavelengths. By setting Bragg gratings with different parameters on different output channels, we can achieve complex wavelength selection and signal processing functions.

[0037] It is worth noting that all the second optical waveguide output channels are arranged in parallel and spaced apart. This layout not only simplifies the chip design and manufacturing process, but also helps to reduce crosstalk between channels and improve signal quality.

[0038] Advanced femtosecond laser etching technology is used in the manufacturing process. The planar waveguide grating 4-1, Bragg grating 4-3 and microcirculator 4-2 are all directly etched on the silicon photonic chip 4 by this technology. Femtosecond laser etching technology has extremely high precision and can accurately control the depth and shape of etching at the nanometer level, which ensures the performance and consistency of each optical component.

[0039] The planar waveguide grating of the present invention utilizes the diffraction, interference and total reflection technology of the grating, and uses photolithography technology to etch an optical waveguide on a silicon-based plane, so that the optical signal is diffracted by the grating and is divided into multiple beams. When two plane waves arrive at the same location, under the condition of meeting the same phase, the two light waves are superimposed and mutually reinforced, so that the light waves are maintained in the waveguide to propagate to form a guided wave. Because of the refractive index of the material, the guided wave beam is restricted to be transmitted in the waveguide, and finally the optical signal branching function is realized. Only when the guided wave is formed and the total reflection condition is met, the optical signal can be transmitted in the waveguide. For a given waveguide structure and the frequency of the incident light, different m values ​​have different solutions for θ1 or β in the equation; Among them, K = k0*(n12-N 2)1 / 2, where N = β / k0 is called the modal refractive index or effective refractive index.

[0040] The Bragg grating of the present invention is a grating with a periodic refractive index change within a certain length range. When the Bragg condition is met, the light signal reflected back from each grating plane is gradually accumulated, and finally a reflection peak is formed in the reverse channel of light transmission. The central wavelength λ is determined by the grating parameters, where ηeff is the refractive index of the medium for light signal transmission to the central wavelength, and ∧ is the grating period.

[0041]

[0042] Can get

[0043] λ=2*η eff *∧

[0044] The present invention utilizes this characteristic of the Bragg grating, and sets Bragg gratings with different parameters to reflect and filter each optical signal output by the planar waveguide grating, and finally obtains multiple optical signals with independent wavelengths; the optical signal is coupled to the silicon photonic integrated chip through a single-core optical fiber array, and the optical signal enters the input waveguide of the planar grating waveguide of the silicon photonic chip and is divided into four through the output waveguide, and each optical signal passes through the Pn-1 port of the silicon photonic microcirculator, and is output through the Pn-2 port of the microcirculator, and enters different Bragg gratings and is output respectively, and the optical signal of a specific wavelength is reflected by the Bragg grating and output through the Pn-3 port of the microcirculator.

[0045] In order to protect these delicate optical structures, the surface of the silicon photonic chip 4 is covered with a cover plate 5. This cover plate can not only protect the chip surface from the influence of the external environment, but also improve the mechanical strength and stability of the entire component.

[0046] A significant advantage of the structural design of the present invention is its versatility and flexibility. By adjusting the parameters of the Bragg grating and the working mode of the microcirculator, a variety of complex optical signal processing functions such as wavelength selection, signal splitting, wavelength conversion, etc. can be achieved. At the same time, since all functions are integrated on a miniaturized silicon photonic chip, the volume of the entire component can be greatly reduced, making it very suitable for space-constrained application scenarios.

[0047] The silicon photonic integrated Bragg grating assembly of the present invention represents an important development direction of optical communication technology. Through high integration and precision design, it realizes complex optical signal processing functions on a miniaturized platform, paving the way for more efficient and flexible optical communication systems in the future.

[0048] Example 2

[0049] This embodiment is attached Figure 3 Taking a four-channel Bragg grating integrated silicon photonic chip as an example, the present invention further explains that a planar waveguide grating structure 4-1, a silicon photonic microcirculator structure 4-2 (a corresponding number of microcirculators are etched according to the number of waveguides output by the planar waveguide grating), a Bragg grating structure 4-3, a Bragg grating structure 4-4, a Bragg grating structure 4-5, and a Bragg grating structure 4-6 are etched on a silicon-based substrate material, and an optical signal is sequentially input from the planar waveguide grating according to the propagation direction and output through the Bragg grating and the circulator, wherein the planar waveguide grating is a 1×N structure, and a multi-wavelength optical signal λ is input. i After passing through the planar waveguide grating, it is divided into multiple optical signals λ i-1 , i-2 , ..., λ i-N Each optical signal is input through the circulator Pn-1 port, and the optical signal is output to the Bragg grating through the circulator Pn-2 port, and then transmitted through the Bragg grating to λ i-1 , i-2 , ..., λ i-N Each Bragg grating is set with different grating period parameters. The optical signal reflected by the Bragg grating will form an independent wavelength. The independent wavelength optical signal returns to the circulator and is output through the circulator P3 port, and finally obtains different wavelengths of λ1, λ2, ..., λ N light signal.

[0050] Attach Figure 3For example, the wavelength obtained by reflection by Bragg grating 4-3 is output as λ1 through circulator port Pn-3, the wavelength obtained by reflection by Bragg grating 4-4 ​​is output as λ2 through circulator port P3, the wavelength obtained by reflection by Bragg grating 4-5 is output as λ3 through circulator port P3, and the wavelength obtained by reflection by Bragg grating 4-6 is output as λ4 through circulator port P3, and so on to obtain optical signals of separate wavelengths of different paths.

[0051] Example 3

[0052] This embodiment discloses an optical module, which uses the silicon optical integrated Bragg grating component disclosed in Example 1, including an LC optical interface 2 and a base plate 1, on which a single-fiber optical fiber array 3, a silicon optical integrated Bragg grating component and an array hyperbolic silicon lens 6 arranged in sequence are arranged. The single-fiber optical fiber array 3 includes a base plate 3-1 with an optical fiber positioning groove, a flat cover plate 3-2 arranged on the base plate 3-1, and a tail end protective glue 3-3.

[0053] The present invention integrates different types of gratings together through silicon photonic integration technology to make them more compact. Each optical signal is transmitted separately, and the transmission between optical fiber signals with separated wavelengths is less affected by interference. Different Bragg grating lengths and periods can be flexibly set according to the layout of the channel to obtain different reflection wavelengths, which is more flexible in communication network applications.

[0054] It should be understood that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0055] It should be understood that those skilled in the art can make improvements or changes based on the above description, and all these improvements and changes should fall within the scope of protection of the appended claims of the present invention.

Claims

1. A silicon optical integrated Bragg grating component, characterized in that: The invention comprises a silicon photonic chip (4), on which a planar waveguide grating (4-1), a Bragg grating (4-3) and a microcirculator (4-2) are arranged, wherein the planar waveguide grating (4-1) comprises at least one optical waveguide input channel and a plurality of first optical waveguide output channels, each first optical waveguide output channel is correspondingly connected to a microcirculator (4-2), and each microcirculator (4-2) comprises two second optical waveguide output channels, and at least one of the second optical waveguide output channels is provided with the Bragg grating (4-3).

2. The silicon optical integrated Bragg grating assembly according to claim 1, characterized in that: The planar waveguide grating (4-1) comprises one optical waveguide input channel and four first optical waveguide output channels.

3. The silicon optical integrated Bragg grating assembly according to claim 1, characterized in that: The second optical waveguide output channels are arranged in parallel and spaced apart.

4. The silicon optical integrated Bragg grating assembly according to claim 1, characterized in that: The planar waveguide grating (4-1), the Bragg grating (4-3) and the microcirculator (4-2) are etched on the silicon photonic chip (4) by femtosecond laser.

5. The silicon optical integrated Bragg grating assembly according to claim 1, characterized in that: The microcirculator (4-2) comprises a P1 port, a P2 port and a P3 port, wherein the P1 port is connected to the first optical waveguide output channel, the P2 port is connected to the second optical waveguide output channel and the Bragg grating (4-3), and the P3 port is connected to the second optical waveguide output channel.

6. The silicon optical integrated Bragg grating assembly according to claim 5, characterized in that: The optical signal is input from the P1 port and output from the P2 port; the optical signal input from the P2 port can only be output from the P3 port.

7. The silicon optical integrated Bragg grating assembly according to claim 1, characterized in that: A cover plate (5) is provided on the silicon photonic chip (4).

8. An optical module, characterized in that: It comprises the silicon photonic integrated Bragg grating component as described in any one of claims 1 to 9.

9. The optical module according to claim 8, characterized in that: It comprises a base plate (1), on which a single-fiber optical fiber array (3), a silicon-optical integrated Bragg grating component and an array hyperbolic silicon lens (6) are arranged in sequence.

10. The optical module according to claim 8, characterized in that: The single-fiber optical fiber array (3) comprises a bottom plate (3-1) with an optical fiber positioning groove, a flat cover plate (3-2) arranged on the bottom plate (3-1), and a tail end protective glue (3-3).

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