An Au-NaYF4:Eu 3+ Optical information storage method using Au array

Abstract

The application discloses a kind of light information storage methods based on Au-NaYF4:Eu 3+ -Au array, according to the product induced by surface plasmon has the "memory" characteristics to the power induced its transformation, first plating a layer of gold island film on glass substrate, then NaYF4:Eu 3+ Nanoparticle is uniformly dropped on gold island film, and gold is sprayed on its surface to form Au-NaYF4:Eu 3+ -Au three-layer film structure with "memory characteristics", finally, Au-NaYF4:Eu 3+ -Au film surface is written in bright and dark controllable light-emitting array, by changing the power of excitation light to collect the fluorescence imaging of each point in the array, the bright and dark state of each point in the array is obtained and corresponds to digital information, so as to realize data reading.The method is simple and easy to operate, easy to quantify, has good application prospect in secret communication, anti-fake and measurement and control technology, and provides a new idea for data security transmission.

Description

Technical Field

[0001] This invention belongs to the field of applied optics technology, specifically relating to a method based on Au-NaYF4:Eu 3+ -Au array optical information storage method. Background Technology

[0002] Humanity has entered the information technology era, and our production and daily life require the processing of massive amounts of data. In recent years, researchers have been dedicated to exploring efficient information storage devices and methods. Compared with traditional magnetic and semiconductor memories, optical information storage offers advantages such as high efficiency, low energy consumption, and long storage life, thus attracting significant attention. Rare earth nanomaterials possess excellent luminescence properties and efficient spectral conversion capabilities. Recently, many attempts have been made to combine photochromism with rare earth ion luminescence. Using re-doped photochromic materials, not only can stored optical information be effectively read, but the photochromism and luminescence can also be adjusted by changing the content and type of rare earth ions. However, due to the poor crystallinity of photochromic materials or lattice incompatibility between rare earth ions and the host matrix, the resolution and signal-to-noise ratio of information reading are limited. Information readout is based on the contrast of emitted colors, requiring not only the calculation of excitation photons but also the calculation of the ratio of certain transition intensities, making information reading no longer simple. Therefore, a simple and easy-to-implement method for preparing optical information storage materials is needed. Summary of the Invention

[0003] The purpose of this invention is to provide a method based on Au-NaYF4:Eu 3+ - An Au array optical information storage method in which each point in the array can quickly switch between enhancement and quenching states to achieve accurate and fast information reading.

[0004] To achieve the above objectives, the technical solution adopted by the present invention includes the following steps:

[0005] 1. Preparation of Au-NaYF4:Eu 3+ Au thin film

[0006] Gold nanoparticle films were deposited on a glass substrate using a thermal evaporation coating apparatus and then annealed to obtain Au nanoisland films; NaYF4:Eu 3+ The white powder was dissolved in deionized water and ultrasonically dispersed until uniform. The resulting dispersion was then dropwise added to the surface of the Au nanoisland membrane and dried to form Au-NaYF4:Eu. 3+ A double-layer film was then formed, and finally, Au particles were uniformly sprayed onto Au-NaYF4:Eu using a gold spraying machine. 3+ Au-NaYF4:Eu is formed on the surface of the bilayer film. 3+ -Au thin film.

[0007] 2. In Au-NaYF4:Eu 3+ High-resolution arrays constructed on Au thin film surfaces

[0008] Under excitation light with a wavelength of 532 nm, high-power P... H and low power P L Two power lasers in Au-NaYF4:Eu 3+ - Irradiate the surface of an Au thin film to construct the desired array.

[0009] 3. Data Reading

[0010] Fluorescence imaging of each point in the array is collected at an excitation power of P, where P is... L <P<P H The on / off state of each point in the array is matched with the corresponding data information.

[0011] In step 1 above, a thermal evaporation coating apparatus is preferably used to deposit a gold nanoparticle thin film with a thickness of 3-5 nm on the cleaned glass substrate, and the vacuum degree of the evaporation is 2.0 × 10⁻⁶. -5 ~2.5×10 -5 Pa, deposition rate is

[0012] In step 1 above, the preferred annealing temperature is 290–310°C and the preferred annealing time is 25–40 seconds.

[0013] In step 1 above, the preferred dispersion is NaYF4:Eu 3+ The concentration of nanoparticles is 0.03–0.05 mol / L.

[0014] In step 1 above, the preferred drying temperature is 40–60°C, forming Au-NaYF4:Eu 3+ NaYF4:Eu bilayer membrane 3+ The thickness is 200–500 nm.

[0015] In step 1 above, Au-NaYF4:Eu is preferred. 3+ The thickness of the Au particles sprayed on the surface of the double-layer film is 8–15 nm.

[0016] In step 2 above, 0.7mW is preferred. <P L <P H <24mW, 5mW <P H -P L .

[0017] In step 3 above, 3mW is preferred. <P H -P.

[0018] The beneficial effects of this invention are as follows:

[0019] 1. This invention utilizes the strong optical confinement and ultrafast thermal response of localized surface plasmon resonance (LSPR) to enhance lattice vibrations in a luminescent crystal, thereby promoting the thermal quenching effect of rare-earth ions and enabling rapid switching between two stable luminescent states. Using a 532nm laser as the irradiation source, a composite structure Y₂O₃:Eu was rapidly obtained. 3+ @Au. By adjusting the irradiation power, it is possible to write, read, and erase all-photon information without requiring additional equipment or operations.

[0020] 2. The thin film prepared by this invention has a large area, is easy to quantify, and has a large data storage capacity. The on / off states of rare-earth luminescent materials are correlated with digital information, thereby achieving digital information storage. This precise and secure plasmonic thermally assisted luminescence technology provides new ideas for various data encryption, anti-counterfeiting, and measurement and control technologies. In particular, this invention constructs Au-NaYF4:Eu 3+ -Au high-resolution rare-earth thin film arrays can stably and quickly read and write a series of data, making data transmission more efficient and convenient. Attached Figure Description

[0021] Figure 1 It is Au-NaYF4:Eu 3+ SEM image of the bilayer membrane.

[0022] Figure 2 It is Au-NaYF4:Eu 3+ - SEM image of Au thin film.

[0023] Figure 3 In Example 1, Au-NaYF4:Eu 3+ - SEM image of a 4×8 dot matrix constructed on the surface of an Au thin film.

[0024] Figure 4 This is a fluorescence imaging image taken when the excitation light power is 2.5mW in Example 1.

[0025] Figure 5 This is a fluorescence imaging image taken when the excitation light power is 7mW in Example 1.

[0026] Figure 6 This is a fluorescence imaging image of the excitation light power of 16mW in Example 1.

[0027] Figure 7 It is Au-NaYF4:Eu in Example 2 3+ - SEM image of a 5×3 dot matrix constructed on the surface of an Au thin film.

[0028] Figure 8This is a fluorescence imaging image taken when the excitation light power is 2.5mW in Example 2.

[0029] Figure 9 This is a fluorescence imaging image taken when the excitation light power is 16mW in Example 2.

[0030] Figure 10 This is a fluorescence imaging image taken when the excitation light power is 7mW in Example 2. Detailed Implementation

[0031] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments, but the scope of protection of the present invention is not limited to these embodiments.

[0032] In the following examples, NaYF4:Eu 3+ The preparation method of the white powder is as follows: In a conical flask, 2.5 mL of a 0.5 mol / L Y(NO3)3 aqueous solution, 0.05 mL of a 0.5 mol / L Eu(NO3)3 aqueous solution, and 7 mL of a 0.2 mol / L NaF aqueous solution are stirred until homogeneous. The mixture is then stirred in a 75°C water bath for 2 hours. After cooling, a white precipitate is obtained by centrifugation. Finally, the precipitate is repeatedly washed with deionized water and alcohol, and dried in a 50°C drying oven for 12 hours to obtain NaYF4:Eu 3+ White powder.

[0033] Example 1

[0034] 1. Preparation of Au-NaYF4:Eu 3+ Au thin film

[0035] A 5 nm thick gold nanoparticle film was deposited on a cleaned glass substrate using a thermal evaporation deposition apparatus (the metal target was a 99.999% pure gold wire, and the deposition vacuum was 2.1 × 10⁻⁶). -5 Pa, deposition rate is The obtained gold nanoparticle film was annealed at 300℃ for 30s to obtain a large-area, relatively uniform Au nanoisland film; then 0.03g of NaYF4:Eu 3+ The white powder was dissolved in 2 mL of deionized water and sonicated in an ultrasonic bath for 10 min to uniformly disperse the rare earth particles, yielding 0.045 mol / L NaYF4:Eu 3+ The resulting dispersion was then dropped onto the surface of the Au nanoisland membrane and dried in a drying oven at 50°C for 3 hours to form Au-NaYF4:Eu. 3+ Double membrane (see) Figure 1 The bilayer membrane contains NaYF4:Eu 3+The thickness is 200-500 nm; finally, Au particles are uniformly sprayed onto Au-NaYF4:Eu using a gold spraying machine. 3+ On the surface of the double-layer film, Au particles with a thickness of 8–15 nm are sprayed, forming Au-NaYF4:Eu. 3+ -Au film (see Figure 2 ).

[0036] 2. In Au-NaYF4:Eu 3+ High-resolution arrays constructed on Au thin film surfaces

[0037] Lasers with power outputs of 6mW and 15mW (wavelength 532nm) were used in Au-NaYF4:Eu 3+ The Au thin film surface was irradiated to construct a 4×8 lattice. The dots in the first row (columns 2, 4, 7, 8), the second row (columns 2, 5, 6, 7), the third row (columns 2, 5, 6, 7), and the fourth row (columns 2, 4, 6, 8) were irradiated with a power of 15 mW, and the remaining dots were irradiated with a power of 6 mW. Au-NaYF4:Eu 3+ The 4×8 dot matrix constructed on the Au thin film surface was characterized by scanning electron microscopy, and the results are shown in [Figure number missing]. Figure 3 .

[0038] 3. Data Reading

[0039] By varying the excitation light power, three different emission patterns were observed when collecting fluorescence images of a 4×8 dot array. When the excitation light power P = 2.5mW (less than 6mW), none of the dots in the array quenched, resulting in a fully bright fluorescence image of the 4×8 dot array. The results are shown in [Figure showing the results]. Figure 4 When the excitation power P = 7mW (greater than 6mW and less than 15mW), the points in the array that undergo phase transitions induced by low-power irradiation will quench. At this time, in the fluorescence imaging of the 4×8 array, only the points in columns 2, 4, 7, and 8 of the first row, columns 2, 5, 6, and 7 of the second row, columns 2, 5, 6, and 7 of the third row, and columns 2, 4, 6, and 8 of the fourth row emit red-orange light. The results are shown in [Figure 1]. Figure 5 When the excitation power P = 16mW (greater than 15mW), all points in the array will quench, and the fluorescence imaging of the 4×8 array will be in a completely extinguished state. The results are shown in [Figure number missing]. Figure 6 .

[0040] When reading encrypted information, fluorescence images of each point in the array are collected, with an excitation power of P = 7mW. The on / off state of the fluorescence images of each point in the array is correlated with the binary characters "1" and "0" to obtain the written string. The first line of data read is 01010011, corresponding to the ASCII code S; the second line of data is 01001110, corresponding to the ASCII code N; the third line of data is 01001110, corresponding to the ASCII code N; the fourth line of data is 01010101, corresponding to the ASCII code U. Finally, the data information read from this 4×8 dot matrix is ​​"SNNU".

[0041] Example 2

[0042] 1. Preparation of Au-NaYF4:Eu 3+ Au thin film

[0043] This step is the same as step 1 in Example 1.

[0044] 2. In Au-NaYF4:Eu 3+ High-resolution arrays constructed on Au thin film surfaces

[0045] Lasers with power outputs of 6mW and 15mW (wavelength 532nm) were used in Au-NaYF4:Eu 3+ - An Au thin film surface was irradiated to construct a 5×3 lattice. The irradiation power for all points in the first row, the points in the third column of the second row, all points in the third row, the points in the third column of the fourth row, and all points in the fifth row was 15 mW, while the remaining points were irradiated with 6 mW. Au-NaYF4:Eu 3+ The 5×3 dot matrix constructed on the Au thin film surface was characterized by scanning electron microscopy, and the results are shown in [Figure number missing]. Figure 7 .

[0046] 3. Data Reading

[0047] When the excitation power P = 2.5mW (less than 6mW), none of the points in the array will quench, and the fluorescence imaging of the 5×3 array will be fully bright. The results are shown in [Figure number missing]. Figure 8 When the excitation power P = 16mW (greater than 15mW), all points in the array will quench, and the fluorescence imaging of the 5×3 array will be in a completely extinguished state. The results are shown in [Figure number missing]. Figure 9 .

[0048] Fluorescence imaging of a 5×3 dot array was performed using a 7mW laser. It was found that all dots in the first row, the third dot in the second row, all dots in the third row, the third dot in the fourth row, and all dots in the fifth row emitted red-orange light; the remaining dots in the array did not emit light. The results are shown in [Figure number missing]. Figure 10The on / off states of fluorescence imaging at each point in the array are collected and mapped to a 5×3 dot matrix, ultimately yielding a patterned number "3".

Claims

1. A method based on Au-NaYF4:Eu 3+ -Au array optical information storage method, characterized in that Includes the following steps: (1) Preparation of Au-NaYF4:Eu 3+ Au thin film Gold nanoparticle films were deposited on a glass substrate using a thermal evaporation coating apparatus and then annealed to obtain Au nanoisland films; NaYF4:Eu 3+ The white powder was dissolved in deionized water and ultrasonically dispersed until uniform. The resulting dispersion was then dropwise added to the surface of the Au nanoisland membrane and dried to form Au-NaYF4:Eu. 3+ A double-layer film was then formed, and finally, Au particles were uniformly sprayed onto Au-NaYF4:Eu using a gold spraying machine. 3+ Au-NaYF4:Eu is formed on the surface of the bilayer film. 3+ -Au thin film; (2) In Au-NaYF4:Eu 3+ High-resolution arrays constructed on Au thin film surfaces Under excitation light with a wavelength of 532 nm, high-power P... H and low power P L Two power lasers in Au-NaYF4:Eu 3+ - Irradiate Au thin film surface to construct the desired array; (3) Data reading Fluorescence imaging of each point in the array is collected at an excitation power of P, where P is... L <P<P H The on / off state of each point in the array is matched with the corresponding data information.

2. The Au-NaYF4:Eu based invention according to claim 1 3+ -Au array optical information storage method, characterized in that In step (1), a thin film of gold nanoparticles with a thickness of 3-5 nm is deposited on the cleaned glass substrate using a thermal evaporation coating apparatus, with a vacuum degree of 2.0 × 10⁻⁶. -5 ~2.5×10 -5 Pa, deposition rate is 3. The Au-NaYF4:Eu based invention according to claim 1 3+ -Au array optical information storage method, characterized in that In step (1), the annealing treatment is performed at a temperature of 290–310°C for 25–40 seconds.

4. The Au-NaYF4:Eu based invention according to claim 1 3+ -Au array optical information storage method, characterized in that In step (1), the dispersion contains NaYF4:Eu 3+ The concentration of nanoparticles is 0.03–0.05 mol / L.

5. The Au-NaYF4:Eu based invention according to claim 1 3+ -Au array optical information storage method, characterized in that In step (1), the drying temperature is 40–60°C, forming Au-NaYF4:Eu 3+ NaYF4:Eu bilayer membrane 3+ The thickness is 200–500 nm.

6. The Au-NaYF4:Eu based invention according to claim 1 3+ -Au array optical information storage method, characterized in that In step (1), the Au-NaYF4:Eu 3+ The thickness of the Au particles sprayed on the surface of the double-layer film is 8–15 nm.

7. The Au-NaYF4:Eu based invention according to claim 1 3+ -Au array optical information storage method, characterized in that In step (2), 0.7mW <P L <P H <24mW, 5mW <P H -P L .

8. The Au-NaYF4:Eu based invention according to claim 1 3+ -Au array optical information storage method, characterized in that In step (3), 3mW <P H -P.

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