阅读说明：本技术 石墨烯等离激元多频带吸收器及其制备方法 (Graphene plasmon multiband absorber and preparation method thereof ) 是由 刘正奇 周进 刘桂强 刘晓山 刘木林 付国兰 于 2020-03-02 设计创作，主要内容包括：本发明公开了石墨烯等离激元多频带吸收器及其制备方法,属于光电材料领域。所述吸收器由下及上依次设有金属衬底层和单层石墨烯,所述金属衬底上表面分布有倾斜空气槽阵列,形成一维金属栅结构。金属衬底上的倾斜空气槽阵列产生了高度集中的等离子体场,同时增强了石墨烯场与电磁波的耦合效应,形成了多波段超窄的完美光吸收。这种多频带吸收器的石墨烯层是由完整的单层石墨烯组成,结构简单易于制造,红外波段光谱可调谐,结构尺寸小,易于集成,可广泛应用于光电传感和光电调控领域。(The invention discloses a graphene plasmon multiband absorber and a preparation method thereof, and belongs to the field of photoelectric materials. The absorber is sequentially provided with a metal substrate layer and a single-layer graphene from bottom to top, and an inclined air groove array is distributed on the upper surface of the metal substrate to form a one-dimensional metal grid structure. The inclined air groove array on the metal substrate generates a highly concentrated plasma field, and simultaneously enhances the coupling effect of the graphene field and the electromagnetic wave, so that multiband ultra-narrow perfect light absorption is formed. The graphene layer of the multiband absorber is composed of complete single-layer graphene, the multiband absorber is simple in structure, easy to manufacture, tunable in infrared band spectrum, small in structural size and easy to integrate, and can be widely applied to the fields of photoelectric sensing and photoelectric regulation.)

1. A graphene plasmon multiband absorber, characterized in that: the graphene layer is connected with the metal substrate; an inclined air groove array is distributed on the metal substrate to form a one-dimensional metal grid structure.

2. The graphene plasmonic multiband absorber of claim 1, wherein: the graphene layer is a single-layer complete graphene.

3. The graphene plasmonic multiband absorber of claim 1 or 2, wherein: the inclined air groove array is formed by arranging inclined air grooves according to a period, and the period is 800 nanometers; the width and height of the air slot are 100 nm and 300 nm, respectively; the inclination angle of the air groove is 45^o。

4. The graphene plasmonic multiband absorber of claim 3, wherein: the thickness of the metal substrate is 400 nm.

5. The graphene plasmonic multiband absorber of claim 4, wherein: the metal substrate is made of gold.

6. The method of making a graphene plasmonic multiband absorber of claim 1, comprising the steps of:

step 1, providing a metal substrate and a silicon wafer;

2, etching an inclined air groove array on the upper surface of the metal substrate by using an etching technology;

3, manufacturing a layer of graphene on a silicon wafer by using a chemical vapor deposition method;

and 4, transferring the graphene manufactured in the step 3 to the upper surface of the metal substrate in the step 2 to obtain the graphene plasmon multiband absorber.

Technical Field

The invention belongs to the field of photoelectric materials, and particularly relates to an absorber and a preparation method thereof.

Background

With the rapid development of modern science and technology, more and more structures with novel optical characteristics and height-adjustable methods are available on the nanoscale, which has attracted people's extensive interest. In recent years, plasmonic metal nanostructures have received much attention due to their local field enhancement and coupling of intense optical fields with illumination light. These characteristics ultimately lead to the emerging potential applications of perfect absorbers and graphene-related near-perfect absorbers, solar energy collection, thermal evaporation techniques, surface enhanced spectroscopy, and sensing. However, graphene optoelectronic devices often involve numerous structural elements and modules, as well as different graphene patterns, which makes graphene devices difficult to manufacture, costly, and not amenable to large-scale fabrication and utilization.

Graphene (Graphene) is a cellular planar film formed from a monolayer of carbon atoms, which is a quasi-two-dimensional material having a thickness of only one atomic layer, also known as monoatomic layer graphite. Graphene has very good electrical conductivity, thermal conductivity, mechanical strength, flexibility and optical characteristics, and has been developed in the fields of physics, materials science, electronic information and computers, aerospace and the like. The conduction electrons on the surface of the graphene can interact with incident photons to form a coupled electromagnetic mode (namely, plasmon resonance), can break through the traditional optical diffraction limit, and can be used as an information carrier in an optical transmission device including an optical coupling device. However, the absorption of the single-layer graphene structure to visible light as well as infrared band light is only 2.3%. The existing research technology has great technical problems in the aspects of how to effectively regulate and control the spectral response characteristics of the graphene structure to light waves or electromagnetic waves, including controllable operation of the graphene structure in spectral notch response of different frequency bands and the like.

Compared with the traditional photoelectric device, the graphene photoelectric device is small in structural size, the response of the device to electromagnetic waves can be tuned by changing the chemical potential of graphene, and the device has excellent tunability.

Disclosure of Invention

In order to solve the problems of few absorption frequency bands, small frequency range, low absorption rate and the like of a graphene wave absorber in the prior art, the invention provides a graphene plasmon multiband absorber, a photoelectric regulation device and a preparation method thereof.

The invention provides a graphene plasmon multiband absorber which comprises a metal substrate and a graphene layer, wherein the graphene layer is connected with the metal substrate; an inclined air groove array is distributed on the metal substrate to form a one-dimensional metal grid structure.

Further, the graphene layer is a single layer of complete graphene.

Furthermore, the inclined air groove array is formed by arranging inclined air grooves according to a period, and the period is 800 nanometers; the width and height of the air slot are 100 nm and 300 nm respectively (the longest side of the inclined air slot is height, and the width is vertical); the inclination angle of the air groove is 45^o。

Further, the thickness of the metal substrate is 400 nm.

Further, the material of the metal substrate is gold.

The preparation method of the graphene plasmon multiband absorber comprises the following steps:

step 1, providing a metal substrate and a silicon wafer;

2, etching an inclined air groove array on the upper surface of the metal substrate by using an etching technology;

3, manufacturing a layer of graphene on a silicon wafer by using a chemical vapor deposition method;

and 4, transferring the graphene manufactured in the step 3 to the upper surface of the metal substrate in the step 2 to obtain the graphene plasmon multiband absorber.

The invention has the beneficial effects that:

1. according to the graphene plasmon multiband absorber, the inclined air groove array on the metal substrate generates a highly concentrated plasma field, the coupling effect of the graphene field and electromagnetic waves is enhanced, and multiband ultra-narrow perfect light absorption is generated in an infrared region;

2. the optical response of the device can be tuned by changing the chemical potential of the graphene, and the device has extremely excellent tuning performance;

3. the invention is insensitive to the incident angle of the incident light, shows excellent absorption stability and has strong inclusion to the incident angle in practical application;

4. the invention has simple structure and small structure size, and is beneficial to the system integration of photoelectric devices; the preparation process is simple, can be used for large-scale manufacture, and can be widely applied to the fields of photoelectric sensing and photoelectric regulation.

Drawings

The present invention will be described in further detail with reference to the accompanying drawings. The following drawings are, however, merely schematic representations of idealized embodiments of the present invention, wherein certain features are shown exaggerated in detail in order to clearly illustrate the structure of devices involved in the present invention, and are not to be considered as schematic representations which strictly reflect the geometric relationships. In addition, the illustrated embodiments of the invention should not be considered limited to the particular shapes of regions illustrated in the drawings. The following drawings are illustrative in nature and should not be considered as limiting the scope of the invention.

Fig. 1 is a schematic structural view of a graphene plasmon multiband absorber according to the present invention.

Fig. 2 is a diagram of light absorption by the graphene plasmon multiband absorber according to the present invention. The thickness of the gold substrate is 400 nm; the period of the air groove on the upper surface of the gold substrate is 800 nm, the width and the height of the air groove are 100 nm and 300 nm respectively, and the inclination angle of the air groove is 45^o(ii) a The chemical potential of graphene is 1.2 eV.

FIG. 3 is a graph of absorption light intensity of a graphene plasmon multiband absorber at an absorption peak position according to chemical potential changes of graphene. The thickness of the gold substrate is 400 nm; the period of the air groove on the upper surface of the gold substrate is 800 nm, the width and the height of the air groove are 100 nm and 300 nm respectively, and the inclination angle of the air groove is 45^o。

Fig. 4 is a diagram of light absorption by the graphene plasmon multiband absorber according to the present invention. The thickness of the gold substrate is 400 nm; the period of the air groove on the upper surface of the gold substrate is 800 nm, the width and the height of the air groove are 100 nm and 300 nm respectively, and the inclination angle of the air groove is 45^o。

Fig. 5 is a graph of light absorption of the graphene plasmon multiband absorber at different incidence angles in the present invention. The thickness of the gold substrate is 400 nm; the period of the air groove on the upper surface of the gold substrate is 800 nm, the width and the height of the air groove are 100 nm and 300 nm respectively, and the inclination angle of the air groove is 45^o。

The reference numerals in fig. 1 explain: 1. metal substrate, 2, inclined air groove, 3, graphene layer.

Detailed Description

The graphene plasmon multiband absorber can be prepared according to the following steps:

step 1, preparing a clean metal substrate and a clean silicon wafer;

step 2, applying an etching technology on the metal substrate to enable the upper surface of the metal substrate to have an inclined air groove structure;

3, manufacturing a layer of graphene on a clean silicon wafer by using a chemical vapor deposition method;

and 4, transferring the graphene manufactured in the step 3 to the metal substrate in the step 2 to obtain the graphene plasmon multiband absorber. The transfer method is at least one of a matrix etching transfer method, a roll-to-roll transfer method, an electrochemical peeling transfer method, a dry transfer method and a mechanical peeling transfer method.

As shown in fig. 1, the prepared graphene plasmon multiband absorber is sequentially provided with a metal substrate and single-layer graphene from bottom to top, and an inclined air groove array is distributed on the upper surface of the metal substrate to form a one-dimensional metal grid structure.

The following describes the technical solution of the present invention in detail with reference to several preferred embodiments and related drawings.