Semi-circular silver nano-metamaterial absorber in the near-infrared band

Abstract

The invention discloses a near-infrared band semi-ring-shaped silver nano-metamaterial absorber, which belongs to the technical field of nano-metamaterial absorbers. The metamaterial absorber is an array structure composed of a plurality of identical units, each unit consisting of a base layer (1), a dielectric layer (2) and a metamaterial layer (3). The base layer (1) and the dielectric layer (2) are both rectangular parallelepipeds, and the metamaterial layer (3) is a semi-ring-shaped body. The dielectric layer (2) is tightly attached above the base layer (1), and the metamaterial layer (3) is arranged above the dielectric layer (2). The metamaterial layer (3) is a semi-ring-shaped body with an opening downwardly arranged in the middle of the dielectric layer (2). The near-infrared band semi-ring-shaped silver nano-metamaterial absorber of the invention has a simple structure, low cost and is easy to process. It only requires three physical structures, namely the base layer, the dielectric layer and the metamaterial layer, to achieve a good absorption effect in the near-infrared band.

Description

Technical Field

[0001] The invention discloses a near-infrared band semi-circular silver nano-metamaterial absorber, which belongs to the technical field of nano-metamaterial absorbers. Background Art

[0002] Metamaterials are artificially designed composite materials that exhibit unusual physical properties not found in natural materials. By adjusting the geometry and dimensions of metamaterials, desired dielectric constants or magnetic permeabilities can be achieved, resulting in a variety of applications in light capture and manipulation.

[0003] Metamaterial absorbers are an important application of metamaterials in optics. They typically feature a three-layer design: a metal-dielectric-metal structure. The top layer consists of a periodically arranged metal nanostructure created by electron beam lithography, while the middle and bottom layers are continuous dielectric and metal layers, respectively.

[0004] Since their introduction, metamaterial absorbers have been widely reported in applications ranging from microwaves to deep ultraviolet wavelengths, demonstrating promising applications in military stealth coatings, photovoltaic materials, and detectors. Currently, metamaterial absorbers are developing towards simpler structures, easier fabrication, and improved absorption performance. Summary of the Invention

[0005] To achieve the above objectives, the present invention designs a near-infrared band semi-circular silver nano-metamaterial absorber with a simple structure, low cost, and easy processing. It only requires three physical structures: a substrate layer, a dielectric layer, and a metamaterial layer to achieve good absorption effects in the near-infrared band.

[0006] The object of the present invention is achieved like this:

[0007] The near-infrared band semi-circular silver nano-metamaterial absorber is an array structure composed of multiple identical units, each unit consisting of a base layer, a dielectric layer and a metamaterial layer; the base layer and the dielectric layer are both rectangular parallelepipeds, and the metamaterial layer is a semi-circular ring; the dielectric layer is closely attached to the base layer, and the metamaterial layer is arranged above the dielectric layer. The metamaterial layer is a semi-circular ring with an opening downwardly arranged in the middle of the dielectric layer.

[0008] The above-mentioned near-infrared band semi-circular silver nano-metamaterial absorber,

[0009] The structural parameters of the base layer 1 are: period w in the x and y directions = 520 nm, thickness h1 = 80 nm;

[0010] The structural parameters of the dielectric layer 2 are: period w in the x and y directions = 520 nm, thickness h2 = 20 nm;

[0011] The structural parameters of the metamaterial layer 3 are: width d=100 nm, inner circle radius r1=50 nm, and outer circle radius r2=100 nm.

[0012] In the above near-infrared band semi-circular silver nano-metamaterial absorber, the base layer is made of silver material, the dielectric layer is made of aluminum oxide material, and the metamaterial layer is made of silver material.

[0013] Beneficial effects:

[0014] First, the semi-circular silver nano-metamaterial absorber in the near-infrared band of the present invention consists of only three physical structures: a substrate layer, a dielectric layer, and a metamaterial layer. Compared with other metamaterial absorbers, it has the advantages of simple structure and easy processing.

[0015] Second, in the near-infrared band semi-circular silver nano-metamaterial absorber of the present invention, the base layer and the metamaterial layer are made of silver material, and the dielectric layer is made of aluminum oxide material, both of which are common and inexpensive materials in life, so the cost is low.

[0016] Third, the semi-circular silver nano-metamaterial absorber in the near-infrared band of the present invention has a good absorption effect in the near-infrared band and has broad application prospects in the fields of optoelectronics and thermal emission. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the three-dimensional structure of the semi-circular silver nano-metamaterial absorber in the near-infrared band of the present invention.

[0018] Figure 2 This is a schematic diagram of the three-dimensional structure of each unit of the semi-circular silver nano-metamaterial absorber in the near-infrared band of the present invention.

[0019] Figure 3 Schematic diagram for defining the dimensional parameters of the substrate layer, dielectric layer, and metamaterial layer.

[0020] Figure 4 It is the transmittance curve of the metamaterial layer at different inner circle radii.

[0021] Figure 5 It is the transmittance curve of the metamaterial layer at different outer circle radii.

[0022] Figure 6 Transmittance curves at different widths of the metamaterial layer.

[0023] In the figure: 1 substrate layer, 2 dielectric layer, 3 metamaterial layer. DETAILED DESCRIPTION

[0024] The specific embodiments of the present invention are further described in detail below with reference to the accompanying drawings. Specific implementation method 1

[0026] The schematic diagram of the structure of the semi-circular silver nano-metamaterial absorber in the near-infrared band under this embodiment is as follows: Figure 1 As shown, it is an array structure composed of multiple identical units. The structural diagram of each unit is as follows Figure 2 As shown, it is composed of a base layer 1, a dielectric layer 2 and a metamaterial layer 3; the base layer 1 and the dielectric layer 2 are both rectangular parallelepipeds, and the metamaterial layer 3 is a semi-circular ring; the dielectric layer 2 is closely attached to the base layer 1, and the metamaterial layer 3 is arranged above the dielectric layer 2, and the metamaterial layer 3 is a semi-circular ring with an opening downwardly arranged in the middle of the dielectric layer 2;

[0027] Wherein, the base layer 1 is made of silver material, the dielectric layer 2 is made of aluminum oxide material, the metamaterial layer 3 is made of silver material, and the size parameters are defined as follows: Figure 3 As shown, specifically:

[0028] The structural parameters of the base layer 1 are: period w in the x and y directions = 520 nm, thickness h1 = 80 nm;

[0029] The structural parameters of the dielectric layer 2 are: period w in the x and y directions = 520 nm, thickness h2 = 20 nm;

[0030] The structural parameters of the metamaterial layer 3 are: width d=100 nm, inner circle radius r1=50 nm, and outer circle radius r2=100 nm. Specific implementation method 2

[0032] In the near-infrared band semi-circular silver nano-metamaterial absorber according to this specific embodiment, the performance of the metamaterial layer 3 under different parameters is simulated.

[0033] The light source is incident from the metamaterial layer 3, the dielectric layer 2 to the substrate layer 1, and FDTD is used for simulation. The simulation results are as follows:

[0034] Simulation experiment 1: Keep h1 = 80nm, h2 = 20nm, w = 520nm, r2 = 100nm, d = 100nm unchanged, and increase the inner radius r1 of the metamaterial layer 3 from 40nm to 56nm in steps of 4nm. The transmittance curve of the semicircular silver nano-metamaterial absorber in the near-infrared band is obtained, as shown in the figure below: Figure 4 As shown, it can be seen that as the inner radius r1 of the metamaterial layer 3 increases, dip shows an obvious red shift and maintains a good absorption effect.

[0035] Simulation experiment 2: keeping h1=80nm, h2=20nm, w=520nm, r1=50nm, d=100nm unchanged, the outer radius r2 of the metamaterial layer 3 is increased from 90nm to 106nm in a step of 4nm, and the transmittance curve of the semicircular silver nano-metamaterial absorber in the near-infrared band is obtained, as shown in Figure 5 As shown, it can be seen that as the outer radius r2 of the metamaterial layer 3 increases, dip shows an obvious red shift and maintains a good absorption effect.

[0036] Simulation experiment 3: keeping h1=80nm, h2=20nm, w=520nm, r1=50nm, r2=100nm unchanged, the width d of the metamaterial layer 3 is increased from 90nm to 106nm in steps of 4nm, and the transmittance curve of the semicircular silver nano-metamaterial absorber in the near-infrared band is obtained, as shown in Fig. Figure 6 As shown, it can be seen that as the width d of the metamaterial layer 3 increases, dip has a slight red shift and maintains a good absorption effect.

[0037] Through three sets of simulation experiments, the structural parameters of the metamaterial layer 3 were finally selected as: width d = 100 nm, inner circle radius r1 = 50 nm, and outer circle radius r2 = 100 nm.

Claims

1. Near-infrared band semi-circular silver nano-metamaterial absorber, which is an array structure composed of multiple identical units, characterized by: Each unit is composed of a base layer (1), a dielectric layer (2) and a metamaterial layer (3); the base layer (1) is made of silver material, the dielectric layer (2) is made of aluminum oxide material, and the metamaterial layer (3) is made of silver material; the base layer (1) and the dielectric layer (2) are both rectangular parallelepipeds, and the metamaterial layer (3) is a semicircular ring; the dielectric layer (2) is tightly attached above the base layer (1), and the metamaterial layer (3) is arranged above the dielectric layer (2); the metamaterial layer (3) is a semicircular ring with an opening downwardly arranged in the middle of the dielectric layer (2).

2. The near-infrared band semi-circular silver nano-metamaterial absorber according to claim 1, characterized in that: The structural parameters of the base layer (1) are: period w in the x and y directions = 520 nm, thickness h1 = 80 nm; The structural parameters of the dielectric layer (2) are: period w in the x and y directions = 520 nm, thickness h2 = 20 nm; The structural parameters of the metamaterial layer (3) are: width d=100 nm, inner circle radius r1=50 nm, outer circle radius r2=100 nm.

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