A chiral signal control device

Abstract

The present invention relates to the technical field of chiral structures, and specifically to a chiral signal control device, comprising a substrate layer, a light-guiding layer, a cavity wall, a chiral structure, an aqueous solution, polystyrene beads, and protrusions; the light-guiding layer is placed on the substrate layer, and the cavity wall is placed around the light-guiding layer to form a container; in the container, the protrusions are periodically distributed on the light-guiding layer; the chiral structure is placed on the top surface of the protrusions; the aqueous solution is placed in the container, and the polystyrene beads are placed in the aqueous solution. The present invention utilizes the photophoresis phenomenon to change the position of the polystyrene beads near the chiral structure and change the dielectric environment near the chiral structure, thereby realizing chiral signal control. Compared with the application of phase change materials, the present invention has the advantage of a large chiral signal control amplitude and has good application prospects in the field of chiral signal control.

Description

Technical Field

[0001] The present invention relates to the technical field of chiral structures, and in particular to a chiral signal control device. Background Art

[0002] Chirality refers to a structural feature in which the mirror image of a structure cannot overlap with itself. Chiral structures have received extensive attention and research due to their special electromagnetic and optical properties. In addition to chiral materials in nature, artificial chiral structures have achieved special properties, such as negative refractive index, circular dichroism, and polarization rotation light, making the preparation of chiral structures a cutting-edge topic in the fields of electromagnetism and optics.

[0003] Researchers have used laser direct writing, electron beam exposure, electron beam evaporation tilt angle deposition, DNA templates and other methods to prepare chiral structures. However, once the chiral structure is prepared, its chiral signal will not be easy to adjust.

[0004] In order to adjust the chiral signal of the chiral structure, researchers use phase change materials. Under the action of external electric or magnetic fields, the temperature inside the material rises, causing the internal structure to transform from amorphous to crystalline, or from crystalline to amorphous, resulting in a change in refractive index, thereby changing the chiral signal of the structure. For example, the authorized patent CN111965849B discloses a controllable chiral structure and control method based on temperature control of GST phase change materials: the structure is composed of periodic units, each unit is composed of GST micro-nano structure, silicon dioxide film and gold substrate, and circular dichroism is achieved in the near-infrared band by preparing a chiral GST array on the silicon dioxide film, and circular dichroism is adjusted by changing the temperature of GST. In the chiral signal regulation based on phase change materials, external factors such as temperature, electric field, and magnetic field have little effect on the refractive index of the phase change material, resulting in a small change in the chiral signal of the chiral structure. Exploring chiral signal regulation devices based on new principles and mechanisms has important practical value. Summary of the invention

[0005] In order to solve the above problems, the present invention provides a chiral signal control device, including a substrate layer, a light-guiding layer, a cavity wall, a chiral structure, an aqueous solution, polystyrene beads, and protrusions; the light-guiding layer is placed on the substrate layer, and the cavity wall is placed around the light-guiding layer to form a container; in the container, the protrusions are periodically distributed on the light-guiding layer; the chiral structure is placed on the top surface of the protrusions; the aqueous solution is placed in the container, and the polystyrene beads are placed in the aqueous solution. Compared with the application of phase change materials, the present invention provides another concept for controlling chiral signals, that is, using the photophoresis phenomenon to change the position of the polystyrene beads near the chiral structure, changing the dielectric environment near the chiral structure, thereby achieving chiral signal control. The chiral signal described in the present invention refers to a circular dichroism signal. Other chiral signals, such as asymmetric transmission and polarization state conversion, have similar properties.

[0006] Furthermore, the material of the substrate layer is silicon dioxide. The material of the substrate layer is silicon dioxide, which is convenient for visible light to pass through. In this way, incident light can be irradiated at the top of the present invention, and outgoing light can be received at the bottom of the present invention, that is, the chiral signal can be determined or realized by the difference in the outgoing light.

[0007] Furthermore, the aqueous solution is a deionized aqueous solution, which has poor conductivity and low ion content, making it easier for the polystyrene balls to move in the aqueous solution.

[0008] Furthermore, the material of the chiral structure is a noble metal. Furthermore, the noble metal is gold or silver. The noble metal chiral structure can achieve strong circular dichroism. In addition, the material of the chiral structure can also be selected as a semiconductor material, such as silicon; the material of the chiral structure can also be selected as a phase change material, such as GST and vanadium dioxide.

[0009] Furthermore, the light guide layer is made of infrared transparent material. Infrared light is input into the light guide layer, propagates into the protrusions, is emitted from the sides of the protrusions, enters the aqueous solution, and irradiates the polystyrene balls in the aqueous solution, so that the polystyrene balls produce photophoresis.

[0010] Furthermore, the material of the light-guiding layer is zinc selenide, which absorbs little infrared light and also little visible light with a longer wavelength, and can transmit not only infrared light but also visible light, thus facilitating the detection of the chiral signal of the present invention.

[0011] Furthermore, the chiral structure is an L-shaped chiral structure. When the photophoresis phenomenon occurs, the dielectric environment of the two arms of the L-shaped chiral structure is changed, thereby changing the circular dichroism of the L-shaped chiral structure.

[0012] Furthermore, the top surface of the protrusion is a rectangle, and one arm of the L-shaped chiral structure is parallel to the side of the rectangle. When the photophoresis phenomenon occurs, the circular dichroism of the L-shaped chiral structure is further changed.

[0013] Furthermore, the distances between the two arms of the L-shaped chiral structure and the two sides of the rectangle are not equal. When the photophoresis phenomenon occurs, the circular dichroism of the L-shaped chiral structure is further changed.

[0014] Beneficial effects of the present invention: The present invention provides a chiral signal control device, comprising a substrate layer, a light-guiding layer, a cavity wall, a chiral structure, an aqueous solution, polystyrene beads, and protrusions; the light-guiding layer is placed on the substrate layer, and the cavity wall is placed around the light-guiding layer to form a container; in the container, the protrusions are periodically distributed on the light-guiding layer; the chiral structure is placed on the top surface of the protrusions; the aqueous solution is placed in the container, and the polystyrene beads are placed in the aqueous solution. The present invention utilizes the photophoresis phenomenon to change the position of the polystyrene beads near the chiral structure and change the dielectric environment near the chiral structure, thereby achieving chiral signal control. Compared with the application of phase change materials, the present invention has the advantage of a large chiral signal control amplitude and has good application prospects in the field of chiral signal control.

[0015] The present invention will be further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic diagram of a chiral signal control device.

[0017] Figure 2 It is a schematic diagram of the arrangement of a chiral structure on the top surface of a protrusion.

[0018] Figure 3 This is a schematic diagram of another chiral structure arranged on the top surface of the protrusion.

[0019] Figure 4 This is a schematic diagram of another chiral signal control device.

[0020] In the figure: 1. base layer; 2. light-guiding layer; 3. cavity wall; 4. chiral structure; 5. polystyrene balls; 6. infrared light reflecting layer; 22. protrusion. DETAILED DESCRIPTION

[0021] In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below with reference to the accompanying drawings and examples.

[0022] Example 1

[0023] The present invention provides a chiral signal control device, such as Figure 1As shown, it includes a substrate layer 1, a light-guiding layer 2, a cavity wall 3, a chiral structure 4, an aqueous solution, polystyrene beads 5, and protrusions 22. The light-guiding layer 2 is placed on the substrate layer 1. The material of the substrate layer 1 is silicon dioxide. The material of the light-guiding layer 2 is an infrared light-transmitting material. The light-guiding layer 2 is prepared on the substrate layer 1 by a physical vapor deposition method, and the specific deposition method can be electron beam evaporation coating or magnetron sputtering coating. The cavity wall 3 is placed around the light-guiding layer 2 and surrounds the light-guiding layer 2 to form a container. In the container, the protrusions 4 are periodically distributed on the light-guiding layer 2; the chiral structure 4 is placed on the top surface of the protrusion 22; the aqueous solution is placed in the container, and the polystyrene beads 5 are placed in the aqueous solution, and the height of the aqueous solution is greater than the height of the chiral structure 4. The thickness of the cavity wall 3 is not limited, and the height of the cavity wall 3 is greater than the height of the chiral structure 4 and the height of the aqueous solution, so that the polystyrene beads 5 are arranged in the aqueous solution. Preferably, the material of the cavity wall 3 is an opaque material, specifically, the material of the cavity wall 3 is a ceramic material. During manufacturing, the cavity wall 3 is adhered to the light guide layer 2 .

[0024] When used, infrared light is input into the light-guiding layer 2, and the infrared light propagates into the protrusion 22, and is emitted from the side of the protrusion 22, enters the aqueous solution, and irradiates the polystyrene beads 5 in the aqueous solution, so that the polystyrene beads 5 produce photophoresis, change the position of the polystyrene beads 5 near the chiral structure 4, and change the dielectric environment near the chiral structure 4, thereby realizing chiral signal regulation. Compared with the application of phase change materials, the chiral signal is regulated from the perspective of the dielectric environment. The position of the polystyrene beads 5 has a large regulation range on the chiral signal of the chiral structure 4, and has good application prospects in the field of chiral signal regulation. Compared with the application of phase change materials, the present invention provides a new concept for regulating chiral signals.

[0025] When measuring the chiral signal of a chiral structure, the incident light is Figure 1 The upper side of the Figure 1 The material of the base layer 1 is selected as silicon dioxide, which is convenient for visible light to pass through. The incident light can be irradiated at the top of the present invention, and the outgoing light can be received at the bottom of the present invention, that is, the chiral signal can be determined or observed by the difference of the outgoing light.

[0026] Of course, the reflection spectrum of the chiral structure can also be detected to measure the reflection characteristics of the chiral structure for different circularly polarized lights.

[0027] In this embodiment, the aqueous solution is selected to be a deionized aqueous solution. The deionized aqueous solution has poor conductivity and low ion content, which facilitates the movement of the polystyrene balls 5 in the aqueous solution, and more sensitively controls the position of the polystyrene balls 5 in the aqueous solution, thereby more sensitively controlling the chiral signal of the device.

[0028] In this embodiment, the periodically arranged protrusions 22 are first prepared on the light guide layer 2 by using methods such as spinning, electron beam exposure, and conventional coating methods, and then the chiral structure 4 is prepared on the protrusions 22 by using the same method. The material of the chiral structure 4 is a noble metal, and the noble metal is gold or silver. Visible light can excite strong localized surface plasmon resonance in the noble metal chiral structure 4, so that the noble metal chiral structure 4 can achieve strong circular dichroism.

[0029] In this embodiment, the material of the light guide layer 2 is zinc selenide. Zinc selenide absorbs little infrared light and also absorbs little visible light with a longer wavelength, and can transmit not only infrared light but also visible light, making it easy to detect the chiral signal of the present invention through the difference in transmitted light.

[0030] In the present invention, by changing the wavelength or intensity of the infrared light coupled into the light-guiding layer 2, the wavelength or intensity of the infrared light emitted from the side of the protrusion 22 can be changed, so that the polystyrene balls 5 can produce different degrees of photophoresis, and the dielectric environment around the chiral structure 4 can be changed to different degrees, thereby regulating the chiral signal of the chiral structure.

[0031] In the present invention, the chiral structure 4 is disposed on the top surface of the protrusion 22. Under the irradiation of visible light, the chiral structure 4 can generate chiral signals such as circular dichroism. On the other hand, the chiral structure 4 can also block infrared light from being emitted from the top surface of the protrusion 22, so that more infrared light is emitted from the side of the protrusion 22. The polystyrene beads 5 can produce more significant photophoresis in the aqueous solution, thereby achieving high-sensitivity chiral signal regulation.

[0032] Example 2

[0033] On the basis of Example 1, Figure 2 As shown, the chiral structure 4 is an L-shaped chiral structure. The top surface of the protrusion 22 is a rectangle, that is, the length and width of the top surface of the protrusion 22 are different, the two arms of the L-shaped chiral structure are parallel to the two sides of the rectangle, and the distances between the two arms of the L-shaped chiral structure and the two sides of the rectangle are equal. When the photophoresis phenomenon occurs, the polystyrene ball 5 changes the dielectric environment of the two arms of the L-shaped chiral structure, thereby changing the circular dichroism of the L-shaped chiral structure. Due to the different lengths and widths of the protrusion 22, the infrared rays emitted from different sides of the protrusion 22 are different, and different degrees of photophoresis phenomena are generated on different sides of the protrusion 22, thereby changing the chiral signal of the L-shaped chiral structure to different degrees. In this embodiment, chiral signal regulation can be achieved by preparing protrusions 22 of different lengths and widths, and the regulation method is simple.

[0034] Example 3

[0035] On the basis of Example 2, Figure 3As shown, the distances between the two arms of the L-shaped chiral structure and the two sides of the rectangle are not equal: the distance between the long side of the protrusion 22 and the arm of the L-shaped chiral structure is short, and the distance between the short side of the protrusion 22 and the arm of the L-shaped chiral structure is long. Since the distances between the two arms of the L-shaped chiral structure and the edge of the protrusion 22 are different, when the photophoresis phenomenon occurs, the distances between the polystyrene ball 5 and the two arms of the L-shaped chiral structure are different, thereby changing the dielectric environment around the two arms of the L-shaped chiral structure to varying degrees. Specifically, a stronger photophoresis phenomenon is generated on the side of the long side of the protrusion 22, the polystyrene ball 5 is closer to the chiral structure 4, and the distance between the chiral structure 4 and the approaching polystyrene ball 5 is smaller; while a weaker photophoresis phenomenon is generated on the side of the short side of the protrusion 22, the polystyrene ball 5 is slightly far away from the chiral structure 4, and since the distance between the chiral structure 4 and the approaching polystyrene ball 5 is slightly far, this leads to more changes in the symmetry of the L-shaped chiral structure, and ultimately changes the circular dichroism of the L-shaped chiral structure more, achieving higher sensitivity chiral signal regulation.

[0036] Example 4

[0037] On the basis of Example 2, Figure 4 As shown, an infrared light reflecting layer 6 is provided on the side away from the L-shaped chiral structure and close to the edge of the protrusion 22. Figure 3 In the embodiment of the present invention, the left arm of the L-shaped chiral structure is close to the edge of the protrusion 22, and the infrared light reflecting layer 6 is arranged on the right side of the protrusion 22. The material of the infrared light reflecting layer 6 is gold or aluminum. The infrared light reflecting layer 6 is in the form of a thin film with a thickness greater than 1 micron to block the infrared light from being emitted from this side. In this way, the polystyrene balls 5 will not gather on this side of the protrusion 22, but will gather more on the other side of the protrusion 22, thereby changing the dielectric environment of one arm of the L-shaped chiral structure more, changing the chiral signal of the chiral structure 4 more, and achieving higher sensitivity chiral signal regulation.

[0038] Example 5

[0039] On the basis of Example 2, the top surface of the protrusion 22 is square, that is, the protrusion 22 is square columnar, and the top surface of the protrusion 22 is inclined. Figure 3 In the embodiment, the left side of the protrusion 22 is low and the right side of the protrusion 22 is high, and the top surface of the protrusion 22 forms an inclined plane. When the infrared light in the light guide layer 2 is coupled into the protrusion 22, the light intensity emitted from different sides of the protrusion 22 is different, resulting in different degrees of photophoresis on different sides of the protrusion 22, changing the symmetry of the L-shaped chiral structure, thereby adjusting the chiral signal of the L-shaped chiral structure. Compared with the above-mentioned embodiment, this embodiment provides another new strategy for regulating chiral signals.

[0040] Example 6

[0041] On the basis of Example 2, the top surface of the protrusion 22 is square, that is, the protrusion 22 is a square column, and the heights of the two arms of the L-shaped chiral structure are different. In this way, the two arms of the L-shaped chiral structure have different blocking capabilities for infrared light, and the infrared light intensity emitted from the vicinity of the two arms of the L-shaped chiral structure is different, and different degrees of photophoresis phenomena are generated near the two arms of the L-shaped chiral structure, which changes the dielectric environment of the two arms of the L-shaped chiral structure to different degrees, and realizes the chiral signal regulation of the device. In this embodiment, it is equivalent to the polystyrene ball 5 being moved in the vertical direction, which changes the coupling between the two arms of the L-shaped chiral structure and the polystyrene ball 5 in the vertical direction, and realizes the regulation in three dimensions, so that the regulation amplitude of the chiral signal is larger, and more sensitive chiral signal regulation can be achieved.

[0042] Example 7

[0043] On the basis of any of the above embodiments, the chiral structure 4 is covered with a two-dimensional material layer, and the material of the two-dimensional material layer is graphene or molybdenum disulfide. On the one hand, the two-dimensional material layer gathers more heat on the surface of the chiral structure 4, achieving a stronger photophoresis phenomenon, and pushing the polystyrene balls 5 to move to the surface of the chiral structure 4; on the other hand, the gap between the two-dimensional material layer and the chiral structure 4 is small, and the two-dimensional material layer and the chiral structure 4 produce strong coupling, gather strong electromagnetic fields, thereby generating heat, and pushing the polystyrene balls 5 to move to the surface of the chiral structure 4. The above two effects both cause the polystyrene balls 5 to move more to the surface of the chiral structure 4, change the dielectric environment of the chiral structure 4 more, and achieve higher sensitivity chiral signal regulation.

[0044] Furthermore, part of the surface of the polystyrene ball 5 is coated with a silicon film. The silicon film has a higher refractive index. When the polystyrene ball 5 moves toward the chiral structure 4, the polystyrene ball 5 changes the dielectric environment around the chiral structure 4 more, achieving a higher sensitivity chiral signal regulation.

[0045] Furthermore, a black cover is provided outside the entire device to prevent the influence of stray light from the external environment on the photophoresis phenomenon.

[0046] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A chiral signal control device, characterized in that: It includes a base layer, a light-guiding layer, a cavity wall, a chiral structure, an aqueous solution, polystyrene beads, and protrusions; the light-guiding layer is placed on the base layer, and the cavity wall is placed around the light-guiding layer to form a container; in the container, the protrusions are periodically distributed on the light-guiding layer; the chiral structure is placed on the top surface of the protrusions; the aqueous solution is placed in the container, and the polystyrene beads are placed in the aqueous solution; when used, infrared light is input into the light-guiding layer, the infrared light propagates into the protrusions, is emitted from the sides of the protrusions, enters the aqueous solution, and irradiates the polystyrene beads in the aqueous solution, so that the polystyrene beads produce photophoresis, change the position of the polystyrene beads near the chiral structure, and change the dielectric environment near the chiral structure, thereby realizing chiral signal regulation.

2. The chiral signal control device according to claim 1, characterized in that: The material of the base layer is silicon dioxide.

3. The chiral signal control device according to claim 1, characterized in that: The aqueous solution is a deionized aqueous solution.

4. The chiral signal control device according to claim 1, characterized in that: The material of the chiral structure is a noble metal.

5. The chiral signal control device according to claim 4, characterized in that: The precious metal is gold or silver.

6. The chiral signal control device according to claim 1, characterized in that: The material of the light guide layer is infrared light-transmitting material.

7. The chiral signal control device according to claim 1, characterized in that: The material of the light guide layer is zinc selenide.

8. The chiral signal control device according to claim 1, characterized in that: The chiral structure is an L-shaped chiral structure.

9. The chiral signal control device according to claim 8, characterized in that: The top surface of the protrusion is a rectangle, and one arm of the L-shaped chiral structure is parallel to a side of the rectangle.

10. The chiral signal control device according to claim 9, characterized in that: The distances between the two arms of the L-shaped chiral structure and the two sides of the rectangle are not equal.

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