Electromagnetic metasurface device

Abstract

The invention relates to the technical field of electromagnetic communication, in particular to an electromagnetic metasurface device. The packaging structure comprises a first packaging layer, a second packaging layer, a dielectric layer, a cavity layer and a structural layer, a first liquid inlet hole, a second liquid inlet hole, a first liquid outlet hole and a second liquid outlet hole are formed in the first packaging layer; the second packaging layer and the first packaging layer are arranged in parallel at intervals; the dielectric layer is located between the first packaging layer and the second packaging layer; the cavity layer is located between the second packaging layer and the dielectric layer and connected with the second packaging layer and the dielectric layer, the cavity layer is provided with a through hole communicating with the first liquid inlet hole and the first liquid outlet hole, and the through hole is used for containing liquid metal; the structural layer is located between the first packaging layer and the dielectric layer and connected with the first packaging layer and the dielectric layer, a plurality of micro-fluidic channels suitable for containing liquid metal are constructed on the structural layer, and the two ends of each micro-fluidic channel communicate with the second liquid inlet hole and the second liquid outlet hole correspondingly. According to the invention, the function flexibility of the device and the regulation degree of freedom can be improved.

Description

Technical Field

[0001] This application relates to the field of electromagnetic communication technology, specifically to an electromagnetic metasurface device. Background Technology

[0002] In the field of modern electromagnetic field manipulation research, the control of electromagnetic wave polarization states is an important branch. Polarization information of electromagnetic waves can be used in materials composition analysis, pharmaceutical component identification, surface morphology, remote control, optical communication encryption, and military defense, among other fields.

[0003] Patent application number CN2022100539806 discloses an electromagnetic metasurface device and its fabrication method. It applies liquid metal materials to the design of reconfigurable metasurface electromagnetic devices. By combining microfluidic technology and rationally designing the microfluidic channel structure of the microfluidic chip, the shape and size of the liquid metal can be changed as needed. This enables ultra-wideband, multi-state performance reconfigurability, ensuring that the device meets different functional requirements in real time under complex application scenarios. However, the electromagnetic boundary in this patent is fixed, and the overall operating mode of the device is singular. Summary of the Invention

[0004] This application provides an electromagnetic metasurface device that achieves synergy and decoupling of local reconfigurability of electromagnetic boundary properties and subwavelength wavefront modulation in the same device by constructing a three-dimensional heterogeneous architecture with a cavity layer, a dielectric layer and a structural layer that are separated by independent fluid interfaces.

[0005] This application is achieved through the following technical solution:

[0006] An electromagnetic metasurface device, comprising:

[0007] A first encapsulation layer is provided, wherein a first liquid inlet, a second liquid inlet, a first liquid outlet, and a second liquid outlet are formed on the first encapsulation layer;

[0008] The second encapsulation layer is arranged in parallel and spaced apart from the first encapsulation layer.

[0009] A dielectric layer, wherein the dielectric layer is located between the first encapsulation layer and the second encapsulation layer;

[0010] A cavity layer is located between the second encapsulation layer and the dielectric layer and is connected to the second encapsulation layer and the dielectric layer respectively. The cavity layer has a through hole communicating with the first liquid inlet hole and the first liquid outlet hole. The through hole is used to contain liquid metal.

[0011] A structural layer is located between the first encapsulation layer and the dielectric layer and is connected to the first encapsulation layer and the dielectric layer respectively. The structural layer is provided with a plurality of microfluidic channels suitable for containing liquid metal, wherein the two ends of the microfluidic channels are respectively connected to the second liquid inlet and the second liquid outlet.

[0012] In some optional embodiments, the medium layer is provided with a first flow-through hole and a second flow-through hole, and the first liquid inlet hole and the first liquid outlet hole are respectively connected to the through hole in the cavity layer through the first flow-through hole and the second flow-through hole.

[0013] In some alternative embodiments, the microfluidic channel is located within the contour region of the via in the normal direction of the dielectric layer.

[0014] In some alternative embodiments, the number of microfluidic channels is configured to be multiple, and the multiple microfluidic channels are independent of each other;

[0015] The number of the second inlet holes and the second outlet holes are equal to the number of the microfluidic channels. The multiple second inlet holes are connected to one end of the multiple microfluidic channels, and the multiple second outlet holes are connected to the other end of the multiple microfluidic channels.

[0016] In some alternative embodiments, the first and second inlet ports are each equipped with an electronic pump.

[0017] In some optional embodiments, the microfluidic channel includes multiple sub-segments, adjacent sub-segments are connected by a flow guide segment, and the sub-segments include a first segment, a second segment and a third segment connected in sequence;

[0018] The lengths of the first and third segments are less than the length of the second segment, and the widths of the first and third segments are greater than the length of the second segment.

[0019] In some alternative embodiments, the length direction of the second segment forms an angle with the line connecting the second inlet and the second outlet.

[0020] In some alternative embodiments, the third segment of the sub-segment is connected to the first end of the adjacent sub-segment via the guide segment.

[0021] In some alternative embodiments, the length direction of the guide section is Z-shaped.

[0022] In some optional embodiments, a flow guiding layer and a liquid storage layer are further disposed sequentially between the cavity layer and the second encapsulation layer;

[0023] The liquid storage layer has a liquid storage cavity of variable size, and the flow guiding layer has a flow guiding hole that connects the through hole of the cavity layer to the liquid storage cavity.

[0024] Compared with the prior art, this application has the following advantages and beneficial effects:

[0025] The electromagnetic metasurface device provided in this application allows the cavity layer to dynamically and independently modulate the equivalent electromagnetic boundary impedance of its corresponding region through the injection and drainage of liquid metal within its vias, enabling local switching between operating modes such as transmission and reflection. Simultaneously, the structural layer located on the other side of the dielectric layer can independently and precisely control the phase and amplitude of high-frequency electromagnetic waves through microfluidic channels. This spatially separated dual-liquid system allows the programming of the device's electromagnetic basis and the editing of the wavefront distribution to be performed in parallel without interference. This solves the inherent limitations of fixed boundary conditions and single functional dimensions in traditional reconfigurable metasurfaces, and improves the device's functional flexibility and control freedom without significantly increasing system complexity. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of the exemplary embodiments of this application, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of this application and should not be considered as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort. In the drawings:

[0027] Figure 1 This is a schematic diagram of the electromagnetic metasurface device structure provided in the embodiments of this application;

[0028] Figure 2 Schematic diagrams of various modes for selectively injecting liquid metal into structural layers and cavity layers provided in embodiments of this application;

[0029] Figure 3 This is a schematic diagram of the structure between the dielectric layer and the second encapsulation layer provided in an embodiment of this application;

[0030] Figure 4 This is a partial cross-sectional structural diagram of the electromagnetic metasurface device provided in an embodiment of this application.

[0031] The attached diagram shows the markings and corresponding component names:

[0032] 1-First encapsulation layer, 2-Structural layer, 3-Dielectric layer, 4-Cavity layer, 5-Second encapsulation layer, 6-Flow guiding layer, 7-Liquid storage layer. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the embodiments and accompanying drawings. The illustrative embodiments and descriptions of this application are only for explaining this application and are not intended to limit this application.

[0034] like Figure 1 As shown, this application embodiment provides an electromagnetic metasurface device, which includes a first encapsulation layer 1, a second encapsulation layer 5, a dielectric layer 3, a cavity layer 4, and a structural layer 2. This indicates that the electromagnetic metasurface device provided in this application embodiment is a multi-layer stacked structure. The first encapsulation layer 1, the structural layer 2, the dielectric layer 3, the cavity layer 4, and the second encapsulation layer 5 can each be configured as a directional plate-like structure. The first encapsulation layer 1, the structural layer 2, the dielectric layer 3, the cavity layer 4, and the second encapsulation layer 5 are sequentially attached to each other and bonded and sealed by pressure-sensitive adhesive.

[0035] The first encapsulation layer 1 is constructed with a first liquid inlet, a second liquid inlet, a first liquid outlet, and a second liquid outlet. There is one first liquid inlet and one second liquid inlet, and one or more second liquid inlets and one or more second liquid outlets. The second liquid inlet and the second liquid outlet are in a one-to-one correspondence, that is, the number of second liquid inlets and the number of second liquid outlets are equal.

[0036] The cavity layer 4 has a through hole that communicates with the first liquid inlet and the first liquid outlet, and the through hole is used to contain liquid metal.

[0037] The structural layer 2 is constructed with several microfluidic channels suitable for containing liquid metal, wherein the two ends of the microfluidic channels are respectively connected to the second liquid inlet and the second liquid outlet.

[0038] In this embodiment, the liquid metal contained in the through-holes and microfluidic channels is gallium indium tin alloy. Compared with traditional solid metals, liquid metals have good metallic conductivity and good liquid fluidity. Compared with the five existing room temperature liquid metals, including francium, rubidium, cesium, mercury and gallium, gallium indium tin alloy is non-radioactive, non-volatile and non-toxic, which can ensure the safety and stability of electromagnetic metasurface devices during use.

[0039] In this embodiment, the first encapsulation layer 1 and the second encapsulation layer 5 may be at least one of PVC, PDMS, and polyimide.

[0040] In this embodiment, the extended shape of the microfluidic channel is not limited to a straight line, curve, broken line, or other irregular shape. The shape of the microfluidic channel determines the structure and size of the metasurface unit, and the structure and size of the unit structure determine the function and wavelength of the metasurface. According to the basic theory of subwavelength electromagnetics, different subwavelength metal microstructures have corresponding resonant response frequencies and impedance matching characteristics. By changing the shape and size of the metasurface unit structure, the physical parameters such as amplitude, polarization, and phase of electromagnetic waves can be effectively controlled. Therefore, microfluidic channels of different shapes can realize different metasurface device functions.

[0041] The electromagnetic metasurface device provided in this application embodiment constructs a multi-layered plate-like stacked structure comprising a first encapsulation layer 1, a structural layer 2, a dielectric layer 3, a cavity layer 4, and a second encapsulation layer 5. Pressure-sensitive adhesive is used for pressure bonding to achieve sealed integration between the layers, forming a three-dimensional architecture with two independent fluid control systems. The through-holes in the cavity layer 4 form a first fluid pathway, used to accommodate and inject or drain liquid metal into localized areas, thereby dynamically modulating the macroscopic electromagnetic boundary conditions of that area and achieving switching of operating modes. Simultaneously, multiple microfluidic channels in the structural layer 2 form a second fluid pathway, allowing independent control of the distribution of liquid metal within each channel, thereby achieving high-resolution phase and amplitude modulation of the electromagnetic wavefront. This achieves decoupling, parallel, and collaborative dynamic reconstruction of the electromagnetic boundary properties and wavefront distribution dimensions within a single integrated device. Figure 2 As shown, when neither cavity layer 4 nor structural layer 2 is injected with liquid metal, as Figure 2 As shown in (a), the overall device is equivalent to a dielectric layer 3, through which incident electromagnetic waves are completely transmitted without any modulation effect on the incident electromagnetic waves; when liquid metal is injected into both the cavity layer 4 and the structural layer 2, as... Figure 2 As shown in (b), the overall device is equivalent to a reflective control device, which can control the polarization state of the incident electromagnetic wave; when liquid metal is not injected into structural layer 2 and liquid metal is injected into cavity layer 4, as... Figure 2 As shown in (c), this device acts as a metal reflector, reflecting all incident electromagnetic waves; when liquid metal is injected into structural layer 2 and not into cavity layer 4, as... Figure 2 As shown in (d), the device is equivalent to a transmission control device, which controls the transmitted electromagnetic waves. Depending on the application scenario, liquid metal can be injected into different microchannels to achieve different control effects. It overcomes the defects of traditional reconfigurable metasurfaces, which are limited in function and control freedom due to the fixed electromagnetic boundary, and improves the device's adaptability and functional flexibility in complex electromagnetic scenarios.

[0042] In some optional embodiments, a first flow passage and a second flow passage are formed on the medium layer 3, and the first liquid inlet and the first liquid outlet are respectively connected to the through hole in the cavity layer 4 through the first flow passage and the second flow passage.

[0043] In this embodiment, by constructing a first flow-through hole and a second flow-through hole on the dielectric layer 3, fluid communication between the first encapsulation layer 1 and the cavity layer 4 is achieved, establishing a reliable, low-resistance, and sealed vertical flow path from the external control interface to the internal functional cavity. This ensures that liquid metal can be precisely and efficiently injected into or discharged from the through-holes of the cavity layer 4 under pressure. While maintaining electromagnetic isolation and mechanical support between functional layers, the three-dimensional integration of the fluid system and optimization of spatial wiring are achieved. This not only ensures the response speed and control accuracy of the electromagnetic boundary reconstruction of the cavity layer 4, but also enhances the structural integrity, encapsulation reliability, and interface hermeticity of the device by integrating the flow-through channel inside the dielectric layer 3, thereby improving the stability and environmental adaptability of the entire reconfigurable metasurface device under long-term dynamic working conditions.

[0044] In some alternative embodiments, the microfluidic channel is located within the contour region of the via in the normal direction of the dielectric layer 3.

[0045] In this embodiment, the microfluidic channels in structural layer 2 are all located within the contour projection area of ​​the through-holes in cavity layer 4. This allows for vertical alignment and coverage of the high-frequency wavefront modulation unit and the low-frequency boundary modulation unit in space. It ensures that the reconfigurable electromagnetic boundary formed by the liquid metal within the through-holes of cavity layer 4 can exert a unified and global electromagnetic influence on all microfluidic channel regions above, providing a consistent and synchronously adjustable physical environment for high-frequency wavefront modulation. The beneficial effects of this design are that it greatly enhances the integrity and synergy of the device's electromagnetic response, avoids performance inhomogeneity or parasitic scattering caused by misalignment between the boundary modulation region and the wavefront modulation region, thereby improving the accuracy and efficiency of beamforming and other functions, and simplifying the electromagnetic modeling and optimization process of multilayer structures.

[0046] In some optional embodiments, the number of microfluidic channels is configured to be multiple, and the multiple microfluidic channels are independent of each other; wherein, the number of second inlet holes and second outlet holes are equal to the number of microfluidic channels, the multiple second inlet holes are connected to one end of the multiple microfluidic channels, and the multiple second outlet holes are connected to the other end of the multiple microfluidic channels.

[0047] In this embodiment, each channel is configured with an independent second inlet and a second outlet, thus constructing a multi-channel independent fluid control system. This allows the morphology (such as length and continuity) of the liquid metal in each microfluidic channel to be manipulated individually and precisely. It achieves high degree of freedom programming of the local phase and amplitude distribution of the metasurface, enabling the flexible generation of complex wavefront distributions. Furthermore, the switching of the states of each channel does not interfere with each other, improving the reconfiguration flexibility and functional diversity of the device.

[0048] In some alternative embodiments, the first and second inlet ports are each equipped with an electronic pump.

[0049] In this embodiment, independent liquid supply sources are configured for structural layer 2 and cavity layer 4, allowing the device to independently or collaboratively adjust its working state and beam characteristics according to different application requirements, with different timing, speed and mode, thereby enhancing the device's dynamic reconstruction response speed, control accuracy and multi-task processing capability; for each microfluidic channel, the liquid metal inlet volume and inlet speed can be independently controlled by their respective electronic pumps, further improving the flexibility of wavefront distribution.

[0050] In some optional embodiments, the microfluidic channel includes multiple sub-segments, adjacent sub-segments are connected by a flow guide segment, and the sub-segments include a first segment, a second segment and a third segment connected in sequence; wherein the length of the first segment and the third segment is greater than the length of the second segment, and the width of the first segment and the third segment is less than the length of the second segment.

[0051] In this embodiment, different electromagnetic resonance characteristics are achieved by using liquid metal segments of different sizes. Narrow and long segments can form inductive characteristics or support specific polarization, while short and wide segments can provide stronger capacitive coupling or broadband response. By continuously changing the liquid metal morphology within a single channel, a rich combination of equivalent circuit parameters can be achieved, thereby covering a wider frequency tuning range or achieving more complex dispersion control on a single channel, thus improving the frequency and functional diversity of a single control unit.

[0052] In some alternative embodiments, the length direction of the second segment forms an angle with the line connecting the second inlet and the second outlet.

[0053] In this embodiment, the length direction of the second segment in the channel is further defined to form a certain angle with the line connecting the second liquid inlet and the second liquid outlet, introducing geometric anisotropy. This makes the resonant structure formed when the liquid metal fills the segment have a specific polarization dependence on the response of electromagnetic waves, thereby increasing the device's ability to control polarization conversion or polarization selection.

[0054] In some alternative embodiments, the third segment of the sub-segment is connected to the first end of the adjacent sub-segment via a guide segment, thereby constructing a serial periodic channel structure with a clear order, ensuring that the liquid metal can form a pattern arrangement with a specific spatial periodicity within the channel.

[0055] In some alternative embodiments, the length direction of the guide section is Z-shaped.

[0056] In this embodiment, the guide section is designed with a Z-shaped orientation to increase the tortuosity and effective length of the fluid path. At the same time, without significantly increasing the overall projected area of ​​the channel, it provides more turning nodes for the flow of liquid metal. On the one hand, it can enhance the controllability of fluid flow and reduce unintended shapes caused by fluid inertia. On the other hand, the Z-shaped turning point itself can act as a small resonance or coupling structure, adding additional design freedom to the electromagnetic response.

[0057] In some alternative embodiments, such as Figures 3-4 As shown, a flow guiding layer 6 and a liquid storage layer 7 are sequentially disposed between the cavity layer 4 and the second encapsulation layer 5. The liquid storage layer 7 has a liquid storage cavity of variable size. For example, a shape memory alloy can be placed at the bottom of the liquid storage cavity. This shape memory alloy expands or contracts in response to a specific temperature, thereby changing the volume of the liquid storage cavity. The flow guiding layer 6 has flow guiding holes that connect the through holes of the cavity layer 4 to the liquid storage cavity. When liquid metal is injected into the cavity layer 4, the liquid storage cavity is filled first, and then the cavity layer 4 is filled to a certain liquid level. The volume of the liquid storage cavity is changed by temperature control, thereby controlling the liquid level of the liquid metal in the cavity layer 4. In other embodiments, the through holes in the cavity layer 4 can be constructed with a large cross-sectional area at one end and a small cross-sectional area at the other end. Thus, when the volume of the liquid storage cavity changes, the liquid surface area of ​​the liquid metal in the through holes also changes accordingly, improving the flexibility of control.

[0058] In actual implementation, the base material is first pretreated, including cutting the base material and applying adhesive.

[0059] A first liquid inlet hole, a first liquid outlet hole, a second liquid inlet hole, and a second liquid outlet hole are cut on the surfaces of the first encapsulation layer 1 and the second encapsulation layer 5 using the micro-machining process of a laser engraving machine.

[0060] The designed microfluidic channel shape is cut out on the surface of structural layer 2 using laser engraving micromachining technology;

[0061] The structure of cavity layer 4 was carved using laser engraving machine micromachining technology;

[0062] Assembly complete;

[0063] Using sodium hydroxide solution to remove the oxide layer from the surface of liquid metal;

[0064] Liquid metal is injected into the microfluidic channel and / or cavity layer 4 using an electronic injection pump and a micro-injection process.

[0065] The specific embodiments described above illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. Although the description of this application is presented in conjunction with some embodiments, this does not mean that the features of this application are limited to this embodiment. On the contrary, the purpose of describing the application in conjunction with embodiments is to cover other options or modifications that may be derived based on the claims of this application. To provide a thorough understanding of this application, many specific details are included in the above description. This application may also be implemented without using these details. Furthermore, to avoid confusion or obscuring the focus of this application, some specific details will be omitted in the description. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other.

[0066] It should be noted that in this specification, similar reference numerals and letters in the above figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the figures, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. In the description of this application, it should be noted that unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two elements. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0067] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. An electromagnetic metasurface device, characterized in that, include: The first encapsulation layer (1) has a first liquid inlet hole, a second liquid inlet hole, a first liquid outlet hole and a second liquid outlet hole. The second encapsulation layer (5) is arranged in parallel with the first encapsulation layer (1) at intervals. A dielectric layer (3) is located between the first encapsulation layer (1) and the second encapsulation layer (5); A cavity layer (4) is located between the second encapsulation layer (5) and the dielectric layer (3) and is connected to the second encapsulation layer (5) and the dielectric layer (3) respectively. The cavity layer (4) has a through hole communicating with the first liquid inlet hole and the first liquid outlet hole. The through hole is used to contain liquid metal. The structural layer (2) is located between the first encapsulation layer (1) and the dielectric layer (3) and is connected to the first encapsulation layer (1) and the dielectric layer (3) respectively. The structural layer (2) is constructed with a plurality of microfluidic channels suitable for containing liquid metal, wherein the two ends of the microfluidic channels are connected to the second liquid inlet and the second liquid outlet respectively.

2. The electromagnetic metasurface device according to claim 1, characterized in that, The medium layer (3) is provided with a first flow hole and a second flow hole. The first liquid inlet and the first liquid outlet are respectively connected to the through hole in the cavity layer (4) through the first flow hole and the second flow hole.

3. The electromagnetic metasurface device according to claim 1, characterized in that, In the normal direction of the dielectric layer (3), the microfluidic channel is located within the contour region of the via.

4. The electromagnetic metasurface device according to claim 1, characterized in that, The number of microfluidic channels is configured to be multiple, and the multiple microfluidic channels are independent of each other; The number of the second inlet holes and the second outlet holes are equal to the number of the microfluidic channels. The multiple second inlet holes are connected to one end of the multiple microfluidic channels, and the multiple second outlet holes are connected to the other end of the multiple microfluidic channels.

5. The electromagnetic metasurface device according to claim 1, characterized in that, The first and second liquid inlets are each equipped with an electronic pump.

6. The electromagnetic metasurface device according to claim 1, characterized in that, The microfluidic channel includes multiple sub-segments, with adjacent sub-segments connected by a flow guide segment. Each sub-segment includes a first segment, a second segment, and a third segment connected in sequence. The lengths of the first and third segments are less than the length of the second segment, and the widths of the first and third segments are greater than the length of the second segment.

7. The electromagnetic metasurface device according to claim 6, characterized in that, The length direction of the second segment forms an angle with the line connecting the second inlet and the second outlet.

8. The electromagnetic metasurface device according to claim 6, characterized in that, The third segment of the sub-segment is connected to the first end of the adjacent sub-segment through the guide segment.

9. The electromagnetic metasurface device according to claim 6, characterized in that, The length of the guide section is Z-shaped.

10. The electromagnetic metasurface device according to claim 1, characterized in that, A flow guide layer (6) and a liquid storage layer (7) are also sequentially disposed between the cavity layer (4) and the second encapsulation layer (5). The liquid storage layer (7) has a liquid storage cavity of variable size, and the flow guiding layer (6) is provided with a flow guiding hole that connects the through hole of the cavity layer (4) to the liquid storage cavity.

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