Circular dichroism optical encryption device based on bionics of tiger structure

Abstract

The invention discloses a bionic circular dichroism optical encryption device based on a tiger structure, and the device comprises a first substrate, a first conductive layer, a first electrode patch, an information encryption layer, a second conductive layer, a second electrode patch, and a second substrate. Wherein the information encryption layer adopts a double-layer Z-shaped structure design to simulate a tiger function, an upper layer fixing structure corresponds to a left half tiger of a palm tube, and a lower layer dynamic rotating structure corresponds to a right half tiger held by a user. A ciphertext transmission system is constructed by regulating and controlling three key parameters of an inclination angle, a rotation angle and an electromagnetic wave incidence angle of the lower layer structure, and steganography information can be accurately decrypted by using a specific CD key only when the three key parameters meet preset matching conditions at the same time. According to the invention, the dynamic adjustable circular dichroism (CD) is innovatively realized, and an optical security system for information encryption is constructed through the bionic design of key matching.

Description

TECHNICAL FIELD

[0001] The application relates to the field of electromagnetic wave modulation, in particular to a circular dichroism optical encryption device based on tiger seal structure bionics. BACKGROUND

[0002] With the rapid development of modern information technology, the explosive growth of data intensifies the challenge of information security. Traditional electronic encryption technology is increasingly constrained by the power bottleneck and quantum computing threat, so it is urgent to develop encryption methods based on new physical mechanisms. Among them, optical encryption technology uses the regulation ability of light waves in polarization state, phase, angular momentum, wavelength and other multidimensional degrees of freedom, which can construct a more complex and more secure protection system than traditional digital encryption, and thus encode and decode target information, opening up a new way for information security communication and storage.

[0003] However, the existing optical encryption device still has many technical defects: first, there are few design schemes for circularly polarized wave incident scenes, and the circular dichroism effect has not been effectively combined to realize high-order information encryption; second, the security level of the traditional encryption system is insufficient, and there is a risk of information leakage.

[0004] These defects limit its function in the field of modern optical information encryption and its wide application in other scenarios. The optical encryption device proposed by the application innovatively draws lessons from the verification principle of ancient tiger seals, and uses the upper and lower two-layer "Z" type structure to realize key matching. The upper structure is fixed, similar to the left half of the tiger seal; the lower structure can be dynamically regulated, corresponding to the right half of the tiger seal. Only when the three regulation parameters (inclination angle, rotation angle, incident angle) are completely matched with the upper structure, can the information be decrypted through CD detection. This bionic design not only retains the verification idea of traditional cryptography, but also combines modern optical regulation technology, effectively improving the security of the encryption system. SUMMARY

[0005] In order to overcome the deficiencies in the prior art, the application proposes a circular dichroism optical encryption device based on tiger seal structure bionics. The device designed by the application can realize a dynamically adjustable circular dichroism (CD) response in the frequency range of 175THz to 215THz. Through precise regulation, the device can realize eight CD regulation intervals (0-0.1, 0.1-0.2, 0.2-0.3, 0.3-0.4, 0.4-0.5, 0.5-0.6, 0.6-0.7, 0.7-0.8), which correspond to the numbers 0-7 respectively, and different number combinations are mapped to corresponding letters through a specific encoding rule, thereby constructing a complete optical key system to realize efficient and reliable information encryption.

[0006] The application is implemented by the following technical solutions:

[0007] A kind of bionics based on tiger seal structure circular dichroism optical encryption device, including first substrate, first conductive layer, first electrode sheet, encryption layer, second conductive layer, second electrode patch, second substrate;Wherein, first substrate, first conductive layer, encryption layer, second conductive layer and second substrate are sequentially arranged from top to bottom, first electrode sheet and second electrode patch are arranged in side, the encryption layer is composed of upper layer "Z" type structure, SiO2 layer and lower layer "Z" type structure, "Z" type structure is formed by the periodic structure of potassium bromide KBr inclined layer and silver Ag inclined layer alternately arranged, the upper surface of the device is its outer surface, electromagnetic wave is incident to the interior of the device through the upper surface.The design of the device makes that left-handed and right-handed circular polarized wave produces different responses, i.e. the device exhibits significant circular dichroism.Wherein, the outer side of the device is packaged by substrate, the material of substrate is glass, and the thickness is 1 μm.

[0008] Further, the arrangement order of silver Ag inclined layer and potassium bromide KBr inclined layer in "Z" type structure follows a specific periodic pattern, wherein the arrangement order of upper layer "Z" type structure medium is (Ag KBr) 3 Ag, and the arrangement order of lower layer "Z" type structure medium is (KBr Ag) 3 KBr. Each "Z" type structure contains 3 periods, each period is composed of one silver Ag inclined layer and one potassium bromide KBr inclined layer, and the last period ends with silver Ag inclined layer and potassium bromide KBr inclined layer respectively, forming a structure with specific optical properties. This periodically arranged structure helps to optimize the modulation performance of the device to electromagnetic waves.

[0009] Further, the dielectric constant of Ag is fitted by Drude model, and the electrical response characteristics of Ag thin film layer in electromagnetic wave frequency band can be accurately simulated by this model. Wherein the plasma frequency is 1.2 × 10 16 rad / s, the damping constant is 1.0 × 10 14 rad / s, the refractive index of KBr is 1.5, and the refractive index of SiO2 is 1.45.

[0010] Further, the refractive index of isotropic medium KBr is 1.5.

[0011] Further, a1=a2=0.2 μm, b1=b2=0.45 μm, c1=c2=0.43 μm, d1=d2=0.24 μm of upper and lower layer "Z" type structure, the thickness of Ag layer and KBr layer of upper and lower layer "Z" type structure is p1=p2=0.046 μm and w1=w2=0.03 μm respectively;The inclination angle γ of upper layer fixed "Z" type structure is 30°, the azimuth rotation angle β is 30°, and the inclination angle of lower layer "Z" type structure has two kinds, φ 1 =30° and φ2 = 45°, azimuth rotation angle has two kinds of δ1= 65° and δ2= 275°. θ is the incident angle of circularly polarized wave, and there are two kinds of positive direction θ1= -20° and θ2= 20°. (Parameter annotation, see Appendix Figure 2 、 Figure 3 ).

[0012] Further, in the frequency band of 175THz~215THz, the device has different responses to the two modes of right-handed circularly polarized wave and left-handed circularly polarized wave electromagnetic wave, and shows significant circular dichroism (CD); specifically, when the lower layer "Z" type structure adopts φ 1 = 30°, δ1= 65°, the circularly polarized wave is incident at θ1= -20°, and the frequency is 193THz, the CD can reach 0.82; at this time, the right-handed circularly polarized wave shows transmission characteristics, and the left-handed circularly polarized wave is suppressed transmission.

[0013] Further, in the near-infrared frequency band of 175THz~215THz, by adjusting the three-dimensional parameter combination of the tilt angle, azimuth rotation angle and circularly polarized wave incident angle of the lower layer "Z" type structure, eight different CD control intervals can be realized: 0~0.1, 0.1~0.2, 0.2~0.3, 0.3~0.4, 0.4~0.5, 0.5~0.6, 0.6~0.7, 0.7~0.8. The device of the application establishes a one-to-one mapping relationship between the angular displacement parameter and the CD interval, forms a high-dimensional optical key space, and thus realizes the security encryption of information.

[0014] Compared with the prior art, the application has the following technical effects:

[0015] (1) The application has obvious circular dichroism, when the lower layer "Z" type structure has geometric parameters φ 1 = 30° and δ1= 65°, at 193THz frequency band, when the circularly polarized wave is incident at θ1= -20°, the structure can realize CD as high as 0.82, which shows that it has strong selective transmission characteristics for left-handed and right-handed circularly polarized waves. Specifically, the right-handed circularly polarized wave has high transmittance, while the left-handed circularly polarized wave is significantly suppressed, so it can be used to construct a differential encoding mechanism based on polarization state in optical information encryption.

[0016] (2) The optical encryption device based on the double-layer "Z" type structure designed by the application can dynamically adjust the tilt angle (φ 1 = 30° or φ 1Eight different CD states can be achieved in the frequency range of 175 THz to 215 THz by changing the angle of rotation (δ1= 45° or δ1= 65° or δ1= 275°) and the angle of incidence (θ1= -20° or θ1= 20°). The CD is divided into eight distinct numerical intervals by amplitude: 0~0.1, 0.1~0.2, 0.2~0.3, 0.3~0.4, 0.4~0.5, 0.5~0.6, 0.6~0.7, 0.7~0.8. Each state is mapped to the numbers 0 to 7 by binary coding (000~111), and further combined into specific letters, realizing the complete information encryption link from optical CD value control to digital information to letter text. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 Schematic diagram of an optical encryption device according to an embodiment of the present application.

[0018] Figure 2 Schematic diagram of an information encryption layer in an optical encryption device according to an embodiment of the present application, the left drawing is a front view and the right drawing is a side view.

[0019] Figure 3 Schematic diagram of the parameters of the upper and lower "Z" shaped structure in the information encryption layer according to an embodiment of the present application.

[0020] Figure 4 Schematic diagram of the transmission of left-handed and right-handed circularly polarized waves with θ1= -20° and the lower "Z" shaped structure with φ 1 = 30° and δ1= 65°.

[0021] Figure 5 CD of the optical encryption device with dynamically adjustable circular dichroism in eight states (000~111) according to an embodiment of the present application.

[0022] Figure 6 Encryption and decryption process of the optical encryption device with dynamically adjustable circular dichroism according to an embodiment of the present application.

[0023] In the figure: 1 - first substrate; 2 - first conductive layer; 3 - first electrode patch; 4 - information encryption layer; 5 - second conductive layer; 6 - second electrode patch; 7 - second substrate; θ is the positive direction of the angle of incidence. DETAILED DESCRIPTION

[0024] In order to describe the technical solutions of the present application in detail, the specific embodiments will be described below with reference to the drawings. It should be pointed out that the embodiments are only used to illustrate the core principles of the present application and are not limited to the present application. Those skilled in the art can make similar technical effects by reasonable modification or equivalent replacement without departing from the concept of the present application, and these embodiments should be considered within the scope of protection of the present application.

[0025] In the present application, technical terms such as "installation", "connection", "connection" and the like should be understood to cover various implementation manners such as direct or indirect, fixed or detachable, contact or non-contact, including but not limited to mechanical fixation, electrical interconnection, signal transmission and functional cooperation, etc. Those skilled in the art can make adaptive adjustments according to actual technical needs. The description of spatial position relationship in the present application is adopted in a broad sense. The expressions such as "above", "upper" and the like not only include the arrangement of direct contact on the top, but also include the arrangement of oblique arrangement or only vertical coordinate higher than another feature; similarly, the expressions such as "below", "below" and the like also cover the arrangement of directly below, obliquely below and vertically lower. The specific implementation of these spatial relationships should be understood in combination with the actual needs of the technical solutions.

[0026] As shown in Figure 1 The present application provides a circular dichroism optical encryption device based on tiger seal structure simulation, which comprises a first substrate, a first conductive layer, a first electrode patch, an encryption layer, a second conductive layer, a second electrode patch and a second substrate. The first substrate, the first conductive layer, the encryption layer, the second conductive layer and the second substrate are sequentially arranged from top to bottom, the first electrode patch and the second electrode patch are arranged on the side surface, and the encryption layer mainly comprises an upper "Z" type structure, a SiO2 layer and a lower "Z" type structure. By adjusting two kinds of inclination angles and two kinds of rotation angles of the lower "Z" type structure, in combination with two kinds of incident angles of electromagnetic waves, eight different structure states can be realized. When the working frequency is 175-215THz, these states cooperate with the upper "Z" type structure to produce a dynamically adjustable CD response, which can cover eight CD interval ranges of 0-0.1, 0.1-0.2, …, 0.7-0.8. Specifically, when the lower "Z" type structure has geometric parameters φ 1 = 30° and δ1= 65°, under the 193THz frequency band, when a circularly polarized wave with θ1= -20° is incident, the structure can realize a CD value as high as 0.82, indicating that it has strong selective transmission characteristics for left-handed and right-handed circularly polarized waves.

[0027] According to the encryption mode specified in the present application, the CD realized by the eight states will be mapped to the numbers 0-7 respectively, and the numbers will be mapped to letters by combining the numbers using the mapping relationship of ASCII code (see Figure 6 ), so as to encrypt and decrypt information.

[0028] like Figure 2 and 3 As shown, the thickness of the upper "Z"-shaped structure is 0.15 μm, the thickness of the SiO2 layer is 0.15 μm, and the thickness of the lower "Z"-shaped structure is 0.15 μm.

[0029] like Figure 4 As shown, when the circularly polarized wave is incident at 193THz with an incident angle of θ1 = -20°, and the lower "Z" structure adopts φ 1 When δ1 = 30° and δ1 = 65°, the transmittance of the right circularly polarized wave is 0.87, the transmittance of the left circularly polarized wave is 0.05, and the CD is 0.82.

[0030] like Figure 5 As shown in the figure, when the frequency of the circularly polarized wave is in the range of 175THz to 215THz, by adjusting the geometric configuration of the lower "Z" structure (including the tilt angle φ 1 / φ 2 and the rotation angle δ1 / δ2), as well as the incident angle of the incident circularly polarized wave (θ1 / θ2), can form eight coding states (binary representation: 000-111), achieving a continuously adjustable circular dichroism response from 0 to 0.8 (CD value interval 0.1). Specifically, at an operating frequency of 195THz, the measured CD values ​​corresponding to these eight states are 0.06(000), 0.14(001), 0.25(010), 0.36(011), 0.43(100), 0.55(101), 0.65(110), and 0.8(111), respectively, demonstrating the ability to control circular dichroism from weak to strong with relatively uniform distribution. This feature makes this device of great application value in the fields of optical encryption and polarization control.

[0031] like Figure 6 As shown, when user 1 wants to encrypt "NJUPT" and send it to user 2, the plaintext "NJUPT" is converted into (φ 2 ,δ2,θ1)(φ 2 ,δ1,θ1),(φ 2 ,δ2,θ1)(φ 2 ,δ2,θ1),(φ 1 ,δ2,θ1)(φ 2 ,δ1,θ2),(φ 2 ,δ2,θ1)(φ 1 ,δ1,θ1),(φ 1 ,δ2,θ1)(φ 2The ciphertext is sent to the user 2. The user 2 regulates the lower layer Z-shaped structure according to the ciphertext content, then measures the corresponding CD response value and carries out numerical mapping according to the ten-bit and single-bit decoding rule, respectively obtains the digital code 15, 11, 34, 27 and 23, and finally correctly parses the digital sequence to the original plaintext "NJUPT" through the pre-defined ASCII code conversion representation, thereby realizing the complete information encryption transmission and decryption process.

[0032] It should be emphasized that the above embodiments are only exemplary and do not limit the present application. Those skilled in the art should understand that the technical solutions can be reasonably modified, adjusted or equivalently replaced without departing from the core idea of the present application, and these modifications should be considered within the protection scope of the present application. The specific meaning of the related terms should be understood in combination with the context of the present application.

Claims

1. A circular dichroism optical encryption device based on the bionic structure of a tiger talisman, characterized in that: It includes a first substrate, a first conductive layer, a first electrode sheet, an encryption layer, a second conductive layer, a second electrode patch, and a second substrate; wherein the first substrate, the first conductive layer, the encryption layer, the second conductive layer, and the second substrate are arranged in sequence from top to bottom, and the first electrode sheet and the second electrode patch are arranged on the side; the encryption layer is composed of an upper "Z"-shaped structure, a SiO2 layer, and a lower "Z"-shaped structure; the "Z"-shaped structure is formed by alternating potassium bromide KBr inclined layers and metallic silver Ag inclined layers to form a periodic structure; the upper surface of the device is its outer surface, and electromagnetic waves are incident into the interior of the device through the upper surface.

2. The circular dichroism optical encryption device based on tiger-shaped bionic structure according to claim 1, characterized in that: The arrangement order of the metallic silver Ag tilted layers and potassium bromide KBr tilted layers in the "Z" structure follows a specific periodic pattern, where the lateral arrangement order of the upper layer is (AgKBr) 3 Ag, the lateral arrangement order of the lower dielectric is (KBrAg) 3 KBr, each "Z"-shaped structure contains 3 periods, each period consists of a metallic silver (Ag) tilt layer and a potassium bromide (KBr) tilt layer, and the last period ends with a metallic silver (Ag) tilt layer and a potassium bromide (KBr) tilt layer, respectively.

3. The circular dichroism optical encryption device based on tiger-shaped bionic structure according to claim 1, characterized in that: The dielectric constant of metallic silver conforms to the Drude model, where the plasma frequency is 1.2×10 16 rad / s, and the damping constant is 1.0×10 14 rad / s, the refractive index of KBr is 1.5, and the refractive index of SiO2 is 1.

45.

4. The circular dichroism optical encryption device based on tiger-shaped bionic structure according to claim 1, characterized in that: The outside of the device is encapsulated by a substrate made of glass with a thickness of 1μm.

5. The circular dichroism optical encryption device based on tiger-shaped bionic structure according to claim 1, characterized in that: The upper and lower "Z"-shaped structures have a1=a2=0.2μm, b1=b2=0.45μm, c1=c2=0.43μm, d1=d2=0.24μm, and the thicknesses of the Ag layer and KBr layer of the upper and lower "Z"-shaped structures are p1=p2=0.046μm and w1=w2=0.03μm respectively; the tilt angle γ of the upper "Z"-shaped structure is 30°, and the azimuth rotation angle β is 30°. The tilt angles of the lower "Z"-shaped structure are φ 1 =30° and φ 2 =45°, there are two rotation angles, namely δ1=65° and δ2=275°; θ is the incident angle of circularly polarized wave, there are two positive directions, namely θ1=-20° and θ2=20°.

6. The circular dichroism optical encryption device based on tiger-shaped bionic structure according to claim 1, characterized in that: In the frequency band of 175THz to 215THz, the device responds differently to the two modes of right-hand circularly polarized waves and left-hand circularly polarized waves, showing significant circular dichroism CD; specifically, when the "Z" structure of the lower layer adopts φ 1 =30°, δ1=65°, the circularly polarized wave is incident at θ1=-20°, and the frequency is 193THz, the CD can reach 0.82; at this time, the right-hand circularly polarized wave shows a transmission characteristic, while the left-hand circularly polarized wave is suppressed from transmitting.

7. The optical encryption device with dynamically adjustable circular dichroism according to claim 1, wherein: In the near-infrared frequency band of 175THz to 215THz, by controlling the three-dimensional parameter combination of the inclination angle, azimuthal rotation angle and incident angle of the circularly polarized wave of the lower "Z"-shaped structure, eight different CD control ranges can be achieved: 0-0.1, 0.1-0.2, 0.2-0.3, 0.3-0.4, 0.4-0.5, 0.5-0.6, 0.6-0.7, and 0.7-0.8.

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