A method for enhancing synchronization stability of multi-layer semiconductor laser networks

Abstract

The present invention relates to a method for enhancing the synchronization stability of a multilayer semiconductor laser network, belonging to the field of communication technology. The present invention obtains an adjacency matrix based on the symmetrical multilayer network topology structure, introduces the adjacency matrix into the Lang-Kobayashi equation, establishes a modified Lang-Kobayashi equation group that describes the dynamic characteristics of the multilayer semiconductor laser network, and then calculates the complex slowly varying electric field amplitude of each layer of laser using the modified Lang-Kobayashi equation group that describes the dynamic characteristics of the multilayer semiconductor laser network. Finally, a cross-correlation function is introduced, and the synchronization quality between lasers is calculated based on the complex slowly varying electric field amplitude using the cross-correlation function. By taking advantage of the symmetrical structure of the independent layers in the multilayer network and changing the inter-layer connection mode of the multilayer laser network, the synchronization stability of the group in the network is enhanced.

Description

Technical Field

[0001] The present invention relates to the field of communication technology, and in particular to a method for enhancing the synchronization stability of a multi-layer semiconductor laser network. Background Art

[0002] With the rapid development of the Internet of Things (IoT) in recent years, the applications of big data, cloud computing, and artificial intelligence have all required massive amounts of information exchange. Furthermore, with the vast communication networks now covering the globe, improving transmission rates and capacity while achieving secure and lossless communication are key goals in the development of modern communication technologies. Optical communication offers advantages such as long transmission distances, cost-effectiveness, the ability to transmit massive amounts of information at once, and high communication speeds, making it an ideal candidate for future communications. In optical communication systems, semiconductor lasers, as light sources, exhibit rich nonlinear dynamics and are easy to operate. They also offer numerous advantages such as small size, high efficiency, low cost, and strong vibration resistance, making them promising candidates for optical chaotic communication. Optical chaotic carriers generated by semiconductor lasers offer advantages such as wide bandwidth, high security, and ease of implementation, and are widely used in random number generation, information encryption, chaotic lidar, and distributed fiber-optic sensing. In secure communication using semiconductor lasers, two lasers are coupled to each other, and the successful decoding of confidential messages based on chaotic synchronization between the two lasers is a key factor in chaotic secure communication. Based on their understanding of mutually injected semiconductor laser technology, many researchers have recently expanded the synchronization scenarios of mutually injected lasers to the more common multi-point-to-multi-point synchronization in practice, and introduced complex network theory to study its chaotic synchronization mechanism. In complex semiconductor laser networks, the lasers in the network can be divided into different synchronization groups based on the inherent symmetry of the network topology. Lasers belonging to the same group can achieve zero-delay synchronization, while the dynamic output of lasers in different groups is less correlated. Coupling synchronization between lasers can successfully decode confidential messages, so ensuring the stability of chaotic synchronization between lasers is a key factor in achieving chaotic secure communication. In addition, because the synchronization characteristics of semiconductor laser networks are similar to those of synaptic neuron networks and other nonlinear network elements, studying how to achieve stable group synchronization can help build optical neural networks and compact laser network systems based on integrated photonic circuits in the future. These works have important theoretical support and practical significance for many fields.

[0003] Problems of enhancing synchronization stability of complex multi-layer semiconductor laser networks: Unlike simple identical network structures, many systems in real life have multi-layer network structures. Nodes within the same layer have the same model or parameters, while the models and parameters of nodes between different layers are different. They are often connected through more complex patterns and interact in multiple ways, resulting in more complex dynamic problems. For example, different neurons in the human brain realize various cognitive functions through the connection of coupling links between layers. For multi-layer semiconductor laser networks, studies have shown that in addition to the interaction between nodes within the same layer, the coupling structure of nodes between different layers plays a vital role in the stability of node synchronization in the network. Therefore, by rationally designing the connection mode between lasers in different layers in a multi-layer network, it is possible to achieve synchronization control of the multi-layer semiconductor laser network, improve synchronization stability, and enhance timeliness in actual application, which has very important theoretical significance and practical value. Summary of the Invention

[0004] The present invention overcomes the deficiencies of the prior art and provides a method for enhancing the synchronization stability of a multi-layer semiconductor laser network.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] A first aspect of the present invention provides a method for enhancing synchronization stability of a multi-layer semiconductor laser network, comprising the following steps:

[0007] Acquiring hierarchical structure information of a multi-layer semiconductor laser network, and constructing an independent layer symmetric topological structure according to the hierarchical structure information of the multi-layer semiconductor laser network;

[0008] Obtaining an adjacency matrix based on the independent layer symmetry topological structure, and introducing the adjacency matrix into the Lang-Kobayashi equation to establish a modified Lang-Kobayashi equation group describing the dynamic characteristics of the multilayer semiconductor laser network;

[0009] The complex slowly varying electric field amplitude of each layer of laser is calculated by using the modified Lang-Kobayashi equations describing the dynamic characteristics of the multilayer semiconductor laser network;

[0010] A cross-correlation function is introduced, and the synchronization quality between the lasers is calculated according to the complex slowly varying electric field amplitude through the cross-correlation function.

[0011] Furthermore, in a preferred embodiment of the present invention, the symmetrical arrangement of nodes belonging to the same synchronization group in the same layer in the independent layer symmetrical topology structure does not intersect with the symmetrical arrangement of nodes in other layers in the network.

[0012] The modified Lang-Kobayashi equations describing the dynamic characteristics of the multilayer semiconductor laser network specifically satisfy the following relationship:

[0013] ,

[0014] ,

[0015] ,

[0016] ,

[0017] In the equations, the superscript x indicates the layer number of the laser; the subscripts m and n indicate the laser number; is the number of lasers in the layer;

[0018] in, Indicates location The complex slowly varying electric field amplitude of the laser m in the layer, Indicates location The complex slowly varying electric field amplitude of the laser m of the layer; is the linewidth enhancement factor, the linewidth enhancement factor of the η layer is set to 5, and the linewidth enhancement factor of the β layer is set to 4; is the gain saturation coefficient, the gain saturation coefficient of the η layer is set to 2.5e-23, and the gain saturation coefficient of the β layer is set to 3.5e-23; represents the optical gain of the laser m in the η layer, represents the optical gain of the laser m in the β layer, The optical gain of laser m in layer x;

[0019] is the optical lifetime, which is equal to 2ps; is the coupling strength within the η layer, is the coupling strength within the β layer, is the interlayer coupling strength; To describe the connection between laser m and laser n in the β layer, To describe the connection between laser m and laser n in layer η, 、 Both are η layers and The connection between laser m and laser n between layers; t is time; is the coupling delay, the value is 1ns; represents the operating frequency of laser n in the β layer, represents the operating frequency of the laser n in the η layer, and its value is ; = ,in represents the frequency detuning between laser m and laser n, ;in , β， Indicates the layer number where the laser is located;

[0020] represents the average carrier density in the active region of laser m within layer x; is the pumping factor, which is 1.5; is the threshold current, and its value is ; Differential gain g = ;Carrier density in transparent state = .

[0021] Furthermore, in a preferred embodiment of the present invention, a cross-correlation function is introduced, and the synchronization quality between the lasers is calculated based on the complex slowly varying electric field amplitude using the cross-correlation function, specifically including:

[0022] When analyzing synchronization stability, the formula for calculating the CCF value between lasers is as follows:

[0023] ,

[0024] is the CCF value between the lasers, indicating the correlation between the two lasers. The larger the value, the better the correlation. When the maximum value is greater than 0.95, it indicates synchronization. is the lag time; and Represents the chaotic time series of the output; P The value of , is the complex slowly varying electric field amplitude of the laser; Indicates the time average.

[0025] A second aspect of the present invention provides a system for enhancing the synchronization stability of a multi-layer semiconductor laser network. The system includes a memory and a processor. The memory contains a program for enhancing the synchronization stability of a multi-layer semiconductor laser network. When the program is executed by the processor, the following steps are implemented:

[0026] Acquiring hierarchical structure information of a multi-layer semiconductor laser network, and constructing an independent layer symmetric topological structure according to the hierarchical structure information of the multi-layer semiconductor laser network;

[0027] Obtaining an adjacency matrix based on the independent layer symmetry topological structure, and introducing the adjacency matrix into the Lang-Kobayashi equation to establish a modified Lang-Kobayashi equation group describing the dynamic characteristics of the multilayer semiconductor laser network;

[0028] The complex slowly varying electric field amplitude of each layer of laser is calculated by using the modified Lang-Kobayashi equations describing the dynamic characteristics of the multilayer semiconductor laser network;

[0029] A cross-correlation function is introduced, and the synchronization quality between the lasers is calculated according to the complex slowly varying electric field amplitude through the cross-correlation function.

[0030] In the system, the symmetrical arrangement of nodes belonging to the same synchronization group in the same layer in the independent layer symmetrical topology structure does not intersect with the symmetrical arrangement of nodes in other layers in the network.

[0031] In this system, the modified Lang-Kobayashi equations describing the dynamic characteristics of the multilayer semiconductor laser network specifically satisfy the following relationship:

[0032] ,

[0033] ,

[0034] ,

[0035] ,

[0036] In the equations, the superscript x indicates the layer number of the laser; the subscripts m and n indicate the laser number; is the number of lasers in the layer;

[0037] in, Indicates location The complex slowly varying electric field amplitude of the laser m in the layer, Indicates location The complex slowly varying electric field amplitude of the laser m of the layer; is the linewidth enhancement factor, the linewidth enhancement factor of the η layer is set to 5, and the linewidth enhancement factor of the β layer is set to 4; is the gain saturation coefficient, the gain saturation coefficient of the η layer is set to 2.5e-23, and the gain saturation coefficient of the β layer is set to 3.5e-23; represents the optical gain of the laser m in the η layer, represents the optical gain of the laser m in the β layer, The optical gain of laser m in layer x;

[0038] is the optical lifetime, which is equal to 2ps; is the coupling strength within the η layer, is the coupling strength within the β layer, is the interlayer coupling strength; To describe the connection between laser m and laser n in the β layer, To describe the connection between laser m and laser n in layer η, 、 Both are η layers and The connection between laser m and laser n between layers; t is time; is the coupling delay, the value is 1ns; represents the operating frequency of laser n in the β layer, represents the operating frequency of the laser n in the η layer, and its value is ; = ,in represents the frequency detuning between laser m and laser n, ;in , β， Indicates the layer number where the laser is located;

[0039] is the average carrier density in the active region of laser m in layer x; is the pumping factor, which is 1.5; is the threshold current, and its value is ; Differential gain g = ;Carrier density in transparent state = .

[0040] In this system, a cross-correlation function is introduced, and the synchronization quality between the lasers is calculated according to the complex slowly varying electric field amplitude through the cross-correlation function, specifically including:

[0041] When analyzing synchronization stability, the formula for calculating the CCF value between lasers is as follows:

[0042] ,

[0043] is the CCF value between the lasers, indicating the correlation between the two lasers. The larger the value, the better the correlation. When the maximum value is greater than 0.95, it indicates synchronization. is the lag time; and Represents the chaotic time series of the output; P The value of , is the complex slowly varying electric field amplitude of the laser; represents the time average; t is the time.

[0044] A third aspect of the present invention provides a computer-readable storage medium, which includes a program for a method for enhancing the synchronization stability of a multi-layer semiconductor laser network. When the program for the method for enhancing the synchronization stability of a multi-layer semiconductor laser network is executed by a processor, the steps of any one of the methods for enhancing the synchronization stability of a multi-layer semiconductor laser network are implemented.

[0045] The present invention solves the defects existing in the background technology and has the following beneficial effects:

[0046] On the one hand, the present invention addresses multi-layer semiconductor laser networks and designs an inter-layer connection scheme that creates an independent-layer symmetric structure. The symmetrical arrangement of nodes within a layer within the same synchronization group does not intersect with the symmetrical arrangements of nodes in other layers of the network, thereby enhancing the group synchronization stability of the multi-layer semiconductor laser network. On the other hand, previous solutions for enhancing the synchronization stability of semiconductor laser networks primarily target simple, homogeneous systems. However, with the information development trend of the Internet of Everything, the entities connected to communication networks are becoming more diverse, the communication tasks to be completed are becoming more complex, and the communication environment and conditions are becoming increasingly variable. Existing solutions struggle to address the synchronization control issues of multi-layer laser networks. Furthermore, since most methods for enhancing synchronization stability rely on parameter configuration, as the number of nodes and links in the network increases, finding the appropriate parameter values ​​for each laser is time-consuming and the control effect is limited, resulting in reduced efficiency. The present invention innovates at a mechanism level by leveraging the advantages of the independent-layer symmetry of the multi-layer network and changing the inter-layer connection scheme of the multi-layer laser network, thereby enhancing the group synchronization stability of the network. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, without paying any creative work, they can also obtain drawings of other embodiments based on these drawings.

[0048] Figure 1 A schematic diagram of a tree-shaped multilayer semiconductor laser network synchronization stability enhancement scheme is shown;

[0049] Figure 2 This is a system diagram of a multi-layer semiconductor laser network synchronization control method scheme;

[0050] Figure 3 is the time intensity sequence diagram of the η layer laser;

[0051] Figure 4 Schematic diagram of the effect of intra-layer coupling strength and inter-layer coupling strength on the synchronization stability of the laser network;

[0052] Figure 5 A schematic diagram showing the effect of changes in interlayer connection patterns on the synchronization stability of the laser network;

[0053] Figure 6 The present invention shows an overall method flow chart of a method for enhancing synchronization stability of a multi-layer semiconductor laser network. DETAILED DESCRIPTION

[0054] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that, in the absence of conflict, the embodiments of the present application and the features therein can be combined with each other.

[0055] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present invention is not limited to the specific embodiments disclosed below.

[0056] While existing methods for enhancing the synchronization stability of semiconductor laser networks can be applied to simple multilayer networks, they fail to consider how different interlayer coupling link structures and the coupling effects between lasers in these layers influence synchronization stability. These methods simply adjust the dynamic output characteristics of the lasers by modifying their own parameters. In practical applications, these methods struggle to effectively control the synchronization characteristics of complex semiconductor laser networks.

[0057] Therefore, a first aspect of the present invention provides a method for enhancing synchronization stability of a multi-layer semiconductor laser network, comprising the following steps:

[0058] S102: Acquire hierarchical structure information of a multi-layer semiconductor laser network, and construct an independent layer symmetric topological structure according to the hierarchical structure information of the multi-layer semiconductor laser network;

[0059] S104: obtaining an adjacency matrix according to the independent layer symmetric topological structure, and introducing the adjacency matrix into the Lang-Kobayashi equation to establish a modified Lang-Kobayashi equation group that describes the dynamic characteristics of the multilayer semiconductor laser network;

[0060] S106: Calculating the complex slowly varying electric field amplitude of each layer of laser using the modified Lang-Kobayashi equations describing the dynamic characteristics of the multilayer semiconductor laser network;

[0061] S108: Introducing a cross-correlation function, and calculating the synchronization quality between the lasers according to the complex slowly varying electric field amplitude using the cross-correlation function.

[0062] like Figure 1 As shown in the figure, for a tree network, nodes in the same layer can achieve synchronization, while nodes in different layers are not synchronized. Laser I generates a chaotic optical signal and injects it into Laser II and Laser III. Simultaneously, the chaotic optical signals generated by Laser II and Laser III are injected into their respective connected lasers. The other lasers operate in the same way. By setting appropriate parameters such as injection intensity, asymmetric injection parameters, bias current, and frequency detuning, high-quality hierarchical chaotic synchronization can be achieved.

[0063] like Figure 2 As shown, for a multi-layer semiconductor laser network, the present invention proposes a solution for enhancing the synchronization stability of the multi-layer semiconductor laser network by changing the inter-layer coupling structure of the multi-layer network. Figure 2 (a) A multilayer network consisting of six semiconductor lasers. The laser parameters within a layer are consistent, but some operating parameters vary between layers. Based on the inherent symmetry of the topology, the lasers in the network are divided into different synchronization groups. In this scheme, the distribution of interlayer coupling links within the multilayer network does not affect the division of laser synchronization groups within a layer. Figure 2 The inter-layer coupling structure of the network in (a) is a layer-dependent symmetric structure. When nodes in a layer are exchanged, in order to keep the adjacency characteristics of the network topology unchanged, that is, not to destroy the inherent symmetry of the network topology, it is necessary to move nodes in different layers at the same time. For example, when Figure 2 In structure (a), if the positions of nodes 2 and 3 in the η layer are swapped, the positions of nodes 5 and 6 in the β layer must be swapped at the same time to ensure that the symmetric characteristics of the topological structure do not change. In order to achieve synchronous control of multi-layer laser networks, this scheme designs a new type of interlayer coupling structure: independent layer symmetry structure. In the independent layer symmetry structure, the symmetric arrangement of nodes belonging to the same synchronization group in the layer does not intersect with the symmetric arrangement of nodes in other layers in the network, that is, they are independent of each other. For example Figure 2 In structure (b), swapping the positions of nodes 2 and 3 on the nth layer does not affect the topological symmetry of the entire multilayer network. This proposal demonstrates through analytical calculations that independent layer symmetry can effectively improve the stability of group synchronization in multilayer laser networks.

[0064] In step S104, in order to more accurately describe the synchronization characteristics in the semiconductor laser network, the adjacency matrix describing the multi-layer network topology is introduced into the Lang-Kobayashi equation to establish a modified Lang-Kobayashi equation group describing the dynamic characteristics of the multi-layer semiconductor laser network:

[0065] In this system, the modified Lang-Kobayashi equations describing the dynamic characteristics of the multilayer semiconductor laser network specifically satisfy the following relationship:

[0066] ,

[0067] ,

[0068] ,

[0069] ,

[0070] In the equations, the superscript x indicates the layer number of the laser; the subscripts m and n indicate the laser number; is the number of lasers in the layer;

[0071] in, Indicates location The complex slowly varying electric field amplitude of the laser m in the layer, Indicates location The complex slowly varying electric field amplitude of the laser m of the layer; is the linewidth enhancement factor, the linewidth enhancement factor of the η layer is set to 5, and the linewidth enhancement factor of the β layer is set to 4; is the gain saturation coefficient, the gain saturation coefficient of the η layer is set to 2.5e-23, and the gain saturation coefficient of the β layer is set to 3.5e-23; represents the optical gain of the laser m in the η layer, represents the optical gain of the laser m in the β layer, The optical gain of laser m in layer x;

[0072] is the optical lifetime, which is equal to 2ps; is the coupling strength within the η layer, is the coupling strength within the β layer, is the interlayer coupling strength; To describe the connection between laser m and laser n in the β layer, To describe the connection between laser m and laser n in layer η, 、 Both are η layers and The connection between laser m and laser n between layers; t is time; is the coupling delay, the value is 1ns; represents the operating frequency of laser n in the β layer, represents the operating frequency of the laser n in the η layer, and its value is ; = ,in represents the frequency detuning between laser m and laser n, ;in , β， Indicates the layer number where the laser is located;

[0073] is the average carrier density in the active region of laser m in layer x; is the pumping factor, which is 1.5; is the threshold current, and its value is ; Differential gain g = ;Carrier density in transparent state = .

[0074] In step S108, in the system, a cross-correlation function is introduced, and the synchronization quality between the lasers is calculated according to the complex slowly varying electric field amplitude using the cross-correlation function, specifically including:

[0075] When analyzing synchronization stability, the formula for calculating the CCF value between lasers is as follows:

[0076] ,

[0077] is the CCF value between the lasers, indicating the correlation between the two lasers. The larger the value, the better the correlation. When the maximum value is greater than 0.95, it indicates synchronization. is the lag time; and Represents the chaotic time series of the output; P The value of , is the complex slowly varying electric field amplitude of the laser; represents the time average; t is the time.

[0078] Among them, the adjacency matrix The connection between lasers in the same layer can be described, where , β ; , When laser m receives optical injection from laser n, =1, otherwise = 0. Similarly, the interlayer interaction between the η layer and the β layer can also be described by the adjacency matrix when there is optical injection. =1, otherwise =0.

[0079] like Figure 2 The adjacency matrix of the structure in (a) is as follows:

[0080] , , ,

[0081] by Figure 2 Take the structure in (a) as an example, Figure 3 As shown, Figure 3 (a) is the case without inter-layer coupling link, that is, the inter-layer coupling strength =0ns -1 . Figure 3 (b) Considering the influence of interlayer coupling strength on the dynamic characteristics of η-layer laser, the interlayer coupling strength =3ns -1 , Figure 3 The values ​​of the η-layer interlayer coupling strength in b(1)~(4) are 3ns -1 , 7ns -1 , 9ns -1 , 13ns -1 . Vertical comparison Figure 3 a(1)~a(4) and Figure 3 b(1) to b(4) show that interlayer coupling can reduce the stability of laser network cluster synchronization. This also shows that for multi-layer semiconductor laser networks, the interaction between lasers in different layers is not conducive to the synchronous control of the laser network. Considering the influence of interlayer coupling links, the present invention designs an interlayer coupling mechanism to effectively enhance the synchronization stability of semiconductor laser networks.

[0082] from Figure 4 It can be seen from the figure that for the η layer, changes in the three different coupling coefficients will affect the synchronization stability of the lasers in the group. First, the interlayer coupling strength The most obvious effect is on the synchronization stability of the laser group in the η layer, followed by the coupling strength within the layer. For the η-layer laser, the weakest coupling coefficient is the intralayer coupling strength of the connecting layer. . Increase the coupling strength of the connection layer will change The dynamic characteristics of the laser in the layer indirectly affect the chaotic output of the laser, so relative to the interlayer coupling strength For example, the intra-layer coupling strength of the connection layer The impact is weak. Figure 5 The effects of different types of coupling strength on group synchronization are shown for different interlayer connection modes. The figure shows that the parameter ranges for achieving stable group synchronization in the η layer vary significantly. The proposed independent layer symmetry structure can effectively expand the parameter range for achieving stable group synchronization, thereby enabling synchronization control of multilayer semiconductor laser networks.

[0083] In actual optical communication networks, communication partners may originate from different networks, and certain environmental configurations may change depending on different operational tasks. Consequently, numerous heterogeneous semiconductor lasers may be present. The connections between these lasers complicate network coupling and compromise network synchronization stability. This invention leverages the symmetric nature of multi-layer network structures to develop a solution that improves the synchronization stability of semiconductor laser networks. This approach, when applied to complex communication networks with diverse nodes, can achieve high-quality and efficient communication while ensuring secure confidential communications.

[0084] Previous solutions for enhancing the synchronization stability of semiconductor laser networks were mainly aimed at systems with simple structures and homogeneity. However, with the information development trend of the Internet of Things, the entities connected to the communication network are more diverse, the communication tasks that need to be completed are more complex, and the communication environment and conditions are more changeable. Existing solutions are difficult to solve the synchronization control problem of multi-layer laser networks. At the same time, since most methods for enhancing synchronization stability depend on parameter configuration, when the number of nodes and links in the network increases, it will take a certain amount of time to find the reasonable parameter value of each laser, and the control effect is limited, which reduces work efficiency. The present invention innovates from a mechanism perspective. By taking advantage of the symmetrical structure of independent layers in a multi-layer network, the inter-layer connection mode of the multi-layer laser network is changed, thereby achieving the enhancement of the group synchronization stability in the network.

[0085] A second aspect of the present invention provides a system for enhancing the synchronization stability of a multi-layer semiconductor laser network. The system includes a memory and a processor. The memory contains a program for enhancing the synchronization stability of a multi-layer semiconductor laser network. When the program is executed by the processor, the following steps are implemented:

[0086] Acquiring hierarchical structure information of a multi-layer semiconductor laser network, and constructing a symmetrical multi-layer network topology structure according to the hierarchical structure information of the multi-layer semiconductor laser network;

[0087] Obtaining an adjacency matrix based on the symmetric multilayer network topology, and introducing the adjacency matrix into the Lang-Kobayashi equation to establish a modified Lang-Kobayashi equation group that describes the dynamic characteristics of the multilayer semiconductor laser network;

[0088] The complex slowly varying electric field amplitude of each layer of laser is calculated by using the modified Lang-Kobayashi equations describing the dynamic characteristics of the multilayer semiconductor laser network;

[0089] A cross-correlation function is introduced, and the synchronization quality between the lasers is calculated according to the complex slowly varying electric field amplitude through the cross-correlation function.

[0090] In the system, the symmetrical arrangement of nodes belonging to the same synchronization group in the same layer in the symmetrical multi-layer network topology structure does not intersect with the symmetrical arrangement of nodes in other layers in the network.

[0091] In this system, the modified Lang-Kobayashi equations describing the dynamic characteristics of the multilayer semiconductor laser network specifically satisfy the following relationship:

[0092] ,

[0093] ,

[0094] ,

[0095] ,

[0096] In the equations, the superscript x indicates the layer number of the laser; the subscripts m and n indicate the laser number; is the number of lasers in the layer;

[0097] in, Indicates location The complex slowly varying electric field amplitude of the laser m in the layer, Indicates location The complex slowly varying electric field amplitude of the laser m of the layer; is the linewidth enhancement factor, the linewidth enhancement factor of the η layer is set to 5, and the linewidth enhancement factor of the β layer is set to 4; is the gain saturation coefficient, the gain saturation coefficient of the η layer is set to 2.5e-23, and the gain saturation coefficient of the β layer is set to 3.5e-23; represents the optical gain of the laser m in the η layer, represents the optical gain of the laser m in the β layer, The optical gain of laser m in layer x;

[0098] is the optical lifetime, which is equal to 2ps; is the coupling strength within the η layer, is the coupling strength within the β layer, is the interlayer coupling strength; To describe the connection between laser m and laser n in the β layer, To describe the connection between laser m and laser n in layer η, 、 Both are η layers and The connection between laser m and laser n between layers; t is time; is the coupling delay, the value is 1ns; represents the operating frequency of laser n in the β layer, represents the operating frequency of the laser n in the η layer, and its value is ; = ,in represents the frequency detuning between laser m and laser n, ;in , β， Indicates the layer number where the laser is located;

[0099] is the average carrier density in the active region of laser m in layer x; is the pumping factor, which is 1.5; is the threshold current, and its value is ; Differential gain g = ;Carrier density in transparent state = .

[0100] In this system, a cross-correlation function is introduced, and the synchronization quality between the lasers is calculated according to the complex slowly varying electric field amplitude through the cross-correlation function, specifically including:

[0101] When analyzing synchronization stability, the formula for calculating the CCF value between lasers is as follows:

[0102] ,

[0103] is the CCF value between the lasers, indicating the correlation between the two lasers. The larger the value, the better the correlation. When the maximum value is greater than 0.95, it indicates synchronization. is the lag time; and Represents the chaotic time series of the output; P The value of , is the complex slowly varying electric field amplitude of the laser; represents the time average; t is the time.

[0104] It should be noted that this system is in accordance with the hardware portion of the method for enhancing the synchronization stability of a multi-layer semiconductor laser network, and the hardware portion can implement the steps of the method for enhancing the synchronization stability of a multi-layer semiconductor laser network.

[0105] A third aspect of the present invention provides a computer-readable storage medium, which includes a program for a method for enhancing the synchronization stability of a multi-layer semiconductor laser network. When the program for the method for enhancing the synchronization stability of a multi-layer semiconductor laser network is executed by a processor, the steps of any one of the methods for enhancing the synchronization stability of a multi-layer semiconductor laser network are implemented.

[0106] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as: multiple units or components can be combined, or can be integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the components shown or discussed can be through some interfaces, and the indirect coupling or communication connection of the devices or units can be electrical, mechanical or other forms.

[0107] The units described above as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units; they may be located in one place or distributed across multiple network units; some or all of the units may be selected according to actual needs to achieve the purpose of the scheme of this embodiment.

[0108] In addition, all functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may be separately used as a unit, or two or more units may be integrated into one unit; the above-mentioned integrated units may be implemented in the form of hardware or in the form of hardware plus software functional units.

[0109] Those skilled in the art will appreciate that all or part of the steps of the above-mentioned method embodiments may be implemented by hardware associated with program instructions, and the aforementioned program may be stored in a computer-readable storage medium. When the program is executed, the program executes the steps of the above-mentioned method embodiments. The aforementioned storage medium includes various media that can store program codes, such as mobile storage devices, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical disks.

[0110] Alternatively, if the integrated units described above are implemented as software modules and sold or used as standalone products, they can also be stored on a computer-readable storage medium. Based on this understanding, the technical solutions of the embodiments of the present invention, or the portion that contributes to the prior art, can be embodied in the form of a software product. This computer software product, stored on a storage medium, includes instructions for enabling a computer device (such as a personal computer, server, or network device) to execute all or part of the methods of the various embodiments of the present invention. The aforementioned storage media include various media capable of storing program code, such as removable storage devices, ROM, RAM, magnetic disks, or optical disks.

[0111] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A method for enhancing synchronization stability of a multi-layer semiconductor laser network, characterized in that: The following steps are involved: Acquiring hierarchical structure information of a multi-layer semiconductor laser network, and constructing an independent layer symmetric topological structure according to the hierarchical structure information of the multi-layer semiconductor laser network; Obtaining an adjacency matrix based on the independent layer symmetry topological structure, and introducing the adjacency matrix into the Lang-Kobayashi equation to establish a modified Lang-Kobayashi equation group describing the dynamic characteristics of the multilayer semiconductor laser network; The complex slowly varying electric field amplitude of each layer of laser is calculated by using the modified Lang-Kobayashi equations describing the dynamic characteristics of the multilayer semiconductor laser network; Introducing a cross-correlation function, and calculating the synchronization quality between the lasers according to the complex slowly varying electric field amplitude through the cross-correlation function; Wherein, the symmetrical arrangement of nodes belonging to the same synchronization group in the same layer in the independent layer symmetrical topology structure does not intersect with the symmetrical arrangement of nodes in other layers in the network; The modified Lang-Kobayashi equations describing the dynamic characteristics of the multilayer semiconductor laser network specifically satisfy the following relationship: ， ， ， ， In the equations, the superscript x indicates the layer number of the laser; the subscripts m and n indicate the laser number; is the number of lasers in the layer; in, Indicates location The complex slowly varying electric field amplitude of the laser m in the layer, Indicates location The complex slowly varying electric field amplitude of the laser m of the layer; is the linewidth enhancement factor, the linewidth enhancement factor of the η layer is set to 5, and the linewidth enhancement factor of the β layer is set to 4; is the gain saturation coefficient, the gain saturation coefficient of the η layer is set to 2.5e-23, and the gain saturation coefficient of the β layer is set to 3.5e-23; represents the optical gain of the laser m in the η layer, represents the optical gain of the laser m in the β layer, The optical gain of laser m in layer x; in, Indicates location The complex slowly varying electric field amplitude of the laser m in the layer, Indicates location The complex slowly varying electric field amplitude of the laser m of the layer; is the linewidth enhancement factor, the linewidth enhancement factor of the η layer is set to 5, and the linewidth enhancement factor of the β layer is set to 4; is the gain saturation coefficient, the gain saturation coefficient of the η layer is set to 2.5e-23, and the gain saturation coefficient of the β layer is set to 3.5e-23; represents the optical gain of the laser m in the η layer, represents the optical gain of the laser m in the β layer, The optical gain of laser m in layer x; represents the average carrier density in the active region of laser m within layer x; is the pumping factor, which is 1.5; is the threshold current, and its value is ; Differential gain g = ;Carrier density in transparent state = 。 2. The method for enhancing synchronization stability of a multi-layer semiconductor laser network according to claim 1, characterized in that: Introducing a cross-correlation function and calculating the synchronization quality between the lasers according to the complex slowly varying electric field amplitude using the cross-correlation function specifically includes: When analyzing synchronization stability, the formula for calculating the CCF value between lasers is as follows: ， is the CCF value between the lasers, indicating the correlation between the two lasers. The larger the value, the better the correlation. When the maximum value is greater than 0.95, it indicates synchronization. is the lag time; and Represents the chaotic time series of the output; P The value of , is the complex slowly varying electric field amplitude of the laser; Indicates the time average.

3. A synchronization stability enhancement system for a multi-layer semiconductor laser network, characterized in that: The system includes a memory and a processor. The memory contains a synchronization stability enhancement method program for a multi-layer semiconductor laser network. When the synchronization stability enhancement method program for a multi-layer semiconductor laser network is executed by the processor, the following steps are implemented: Acquiring hierarchical structure information of a multi-layer semiconductor laser network, and constructing an independent layer symmetric topological structure according to the hierarchical structure information of the multi-layer semiconductor laser network; Obtaining an adjacency matrix based on the independent layer symmetry topological structure, and introducing the adjacency matrix into the Lang-Kobayashi equation to establish a modified Lang-Kobayashi equation group describing the dynamic characteristics of the multilayer semiconductor laser network; The complex slowly varying electric field amplitude of each layer of laser is calculated by using the modified Lang-Kobayashi equations describing the dynamic characteristics of the multilayer semiconductor laser network; Introducing a cross-correlation function, and calculating the synchronization quality between the lasers according to the complex slowly varying electric field amplitude through the cross-correlation function; Wherein, the symmetrical arrangement of nodes belonging to the same synchronization group in the same layer in the independent layer symmetrical topology structure does not intersect with the symmetrical arrangement of nodes in other layers in the network; The modified Lang-Kobayashi equations describing the dynamic characteristics of the multilayer semiconductor laser network specifically satisfy the following relationship: ， ， ， ， In the equations, the superscript x indicates the layer number of the laser; the subscripts m and n indicate the laser number; is the number of lasers in the layer; in, Indicates location The complex slowly varying electric field amplitude of the laser m in the layer, Indicates location The complex slowly varying electric field amplitude of the laser m of the layer; is the linewidth enhancement factor, the linewidth enhancement factor of the η layer is set to 5, and the linewidth enhancement factor of the β layer is set to 4; is the gain saturation coefficient, the gain saturation coefficient of the η layer is set to 2.5e-23, and the gain saturation coefficient of the β layer is set to 3.5e-23; represents the optical gain of the laser m in the η layer, represents the optical gain of the laser m in the β layer, The optical gain of laser m in layer x; is the optical lifetime, which is equal to 2ps; is the coupling strength within the η layer, is the coupling strength within the β layer, is the interlayer coupling strength; To describe the connection between laser m and laser n in the β layer, To describe the connection between laser m and laser n in layer η, 、 Both are η layers and The connection between laser m and laser n between layers; t is time; is the coupling delay, the value is 1ns; represents the operating frequency of laser n in the β layer, represents the operating frequency of the laser n in the η layer, and its value is ; = ,in represents the frequency detuning between laser m and laser n, ;in , β， Indicates the layer number where the laser is located; is the average carrier density in the active region of laser m in layer x; is the pumping factor, which is 1.5; is the threshold current, and its value is ; Differential gain g = ;Carrier density in transparent state = .

4. The synchronization stability enhancement system of a multi-layer semiconductor laser network according to claim 3, characterized in that: Introducing a cross-correlation function and calculating the synchronization quality between the lasers according to the complex slowly varying electric field amplitude using the cross-correlation function specifically includes: When analyzing synchronization stability, the formula for calculating the CCF value between lasers is as follows: ， is the CCF value between the lasers, indicating the correlation between the two lasers. The larger the value, the better the correlation. When the maximum value is greater than 0.95, it indicates synchronization. is the lag time; and Represents the chaotic time series of the output; P The value of , is the complex slowly varying electric field amplitude of the laser; represents the time average; t is the time.

5. A computer-readable storage medium, characterized in that The computer-readable storage medium includes a program for a method for enhancing the synchronization stability of a multi-layer semiconductor laser network. When the program is executed by a processor, the steps of the method for enhancing the synchronization stability of a multi-layer semiconductor laser network as described in any one of claims 1 to 3 are implemented.

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