Color router for photon momentum control and preparation method thereof

Abstract

The invention relates to a color router for photon momentum control and a preparation method thereof. The color router is composed of a metal nano antenna, a carbon nano tube film and a printed circuit board. When an electron beam excites the edge of the metal nano antenna, green light and red light components emitted by a far field are distributed along different propagation directions, and when an impact position is located at the center, a non-split pattern is generated. In addition, the conversion of the characteristic radiation direction can be triggered by controlling the electron beam excitation position. The active modulation of the dichroic photon splitting can be effectively realized by adjusting the excitation position and changing the far-field interference of the dipole moment and the quadrupole moment. According to the invention, a pleasant platform is provided for controlling the photon momentum on the nanoscale, and a way is laid for the quantum information technology and the integrated photon system in the future.

Description

Technical Field

[0001] The invention relates to a color router for photon momentum manipulation and a preparation method thereof, belonging to the technical field of micro-nano optics. Background Art

[0002] Optical routing technology, with its active manipulation of light fields and high processing speed, has been successfully applied to modern signal transmission, imaging, storage, cryptography and other fields. In the development of photon manipulation technology, it is very important to find a suitable method with high integration and large storage capacity to meet the needs of information transmission and processing applications. Faced with these requirements, color science of multi-frequency channels provides a promising method to achieve large information encoding capabilities, and controlling photon momentum at the nanoscale has been proven to be feasible. Therefore, precise modulation of photons in the frequency domain and spatial domain is beneficial to optical information applications.

[0003] The color routing effect provides a unique way to control the momentum of photons to efficiently utilize the spectrum in both the frequency and spatial domains. In the study of wavefront modulation, color routers separate light of different frequencies into different directions for optical manipulation of multi-frequency channels such as photonic crystal waveguides and frequency-encoded quantum information processing. Since photons are efficient information carriers with high robustness and large capacity, color routers that manipulate the momentum of photons in multi-frequency channels can be applied to high-dimensional, low-crosstalk optical information encoding and encryption. However, due to the lack of flexible manipulation at the nanoscale, this remains difficult to further integrate for on-chip applications. Therefore, an effective solution needs to be proposed to fully realize its potential in optical information applications. Summary of the invention

[0004] The technical solution of the present invention is: to overcome the shortcomings of the prior art, to propose a color router for photon momentum manipulation and a preparation method thereof, which is an optical router excited by an electron beam at a subwavelength scale to modulate the momentum of two-color photons. When the electron beam of the on-chip source hits the edge of the gold nanoantenna, the green and red light components of the far-field emission are distributed along different propagation directions, and when the impact position is located at the center, a non-split pattern is observed. In addition, the conversion of the characteristic radiation direction can be triggered by controlling the electron beam impact position. By reasonably adjusting the excitation position and changing the far-field interference of the dipole moment and the quadrupole moment, the active modulation of the splitting of two-color photons can be effectively achieved. Electron beam regulation such as cathode luminescence, as a high-resolution excitation method, overcomes the diffraction limit of light and has been successfully applied to electromagnetic field research at the subwavelength scale. Under electron beam excitation, the subwavelength displacement of the impact position can directly adjust the distribution of the electron localized state density of the excited object, prompting the change of the far-field emission pattern. This technology overcomes the light diffraction limit and can be used to control the subwavelength-scale electron-induced color router.

[0005] The technical solution of the present invention is as follows:

[0006] A color router for photon momentum manipulation, the color router comprising a cross-shaped metal nanoantenna, a carbon nanotube film and a printed circuit board;

[0007] The metal is aluminum, gold or silver;

[0008] The cross-shaped metal nanoantenna is formed by placing two rectangular metal nanoantennas perpendicular to each other, and the rectangular metal nanoantenna has a length of 200nm to 600nm, a width of 50nm to 100nm, and a thickness of 50nm to 100nm;

[0009] The cross-shaped metal nanoantenna is located on the upper surface of the carbon nanotube film;

[0010] The carbon nanotube film is located on the upper surface of the printed circuit board;

[0011] The printed circuit board is integrated with a programmable gate array for controlling the electron beam excitation position, and further controlling the radiation direction of the red and green light. The printed circuit board is etched with array-arranged excitation units, each of which includes five emission cathodes and five gates. A programmable gate array is integrated under each emission cathode to achieve flexible adjustment and rapid response of the emission cathode. The programmable gate array is used to control the level shifter of each excitation unit, and the programmable gate array adopts vertical and horizontal scanning circuits. When the emission cathode excites different positions of the carbon nanotube film above it, the electrons on the carbon nanotube film are enriched and further emitted to the cross-shaped metal nanoantenna, so as to achieve electron beam excitation with nanometer-level precision.

[0012] The scattering intensity I of the color router when excited by an electron beam is:

[0013]

[0014] Among them, P, M, T, Q αβ 、M αβ and T αβ They correspond to electric dipole, magnetic dipole, circular dipole, electric quadrupole, magnetic quadrupole, and circular quadrupole, respectively. c is the speed of light in a vacuum, ω is the angular frequency, O represents the harmonic minimum term, and α and β are the horizontal and vertical coordinates in the orthogonal coordinate system.

[0015] The printed circuit board can regulate the radiation direction of photons. When the electron beam on the printed circuit board hits the edge of the cross-shaped metal nanoantenna, the green and red components of the far-field emission are distributed along different propagation directions. When the electron beam on the printed circuit board hits the center of the cross-shaped metal nanoantenna, the green and red components of the far-field emission are distributed along the same propagation direction, that is, a non-split pattern is observed.

[0016] The method for preparing a cross-shaped metal nanoantenna is:

[0017] In the first step, a metal layer is deposited on a substrate using an electron beam evaporator, and then a positive resist is spin-coated on the metal layer and etched using an electron beam lithography process to form a cross-shaped metal nanostructure.

[0018] In the second step, the cross-shaped metal nanostructure formed in the first step is irradiated with argon ions to remove the residual polymethyl methacrylate;

[0019] The third step is to immerse the cross-shaped metal nanostructure obtained in the second step in ethanol, clean it in the ethanol with ultrasound, and then dry it in an oven. After drying, a commercial polydimethylsiloxane solution is cast on the dried cross-shaped metal nanostructure, and finally degassed and cured in a vacuum oven to obtain a nanostructured polydimethylsiloxane film, and the nanostructured polydimethylsiloxane film is peeled off from the substrate to obtain a cross-shaped metal nanoantenna;

[0020] The substrate material is silicon dioxide or silicon;

[0021] The method of transferring the carbon nanotube film to the upper surface of the printed circuit board is:

[0022] Step 1, transferring the carbon nanotube film onto a substrate and forming a strip array by reactive ion etching;

[0023] Step 2, patterning the carbon nanotube film formed into a strip array in step 1 by electron beam lithography;

[0024] Step 3, performing electron beam evaporation deposition of substrate material on the pattern of step 2;

[0025] Step 4, peeling the carbon nanotube film obtained in step 3 off the substrate;

[0026] Step 5. In order to improve the alignment accuracy, electron beam lithography and electron beam evaporation are used to create marks on the carbon nanotube film peeled off in step 4, and then the marked carbon nanotube film is transferred to the printed circuit board. During the transfer, the substrate material deposited on the carbon nanotube film faces the printed circuit board. Finally, hydrofluoric acid is used to selectively etch the substrate material and the emission cathode under the carbon nanotube film.

[0027] The center position of the prepared cross-shaped metal nanoantenna is aligned with the created mark and transferred to the carbon nanotube film.

[0028] Beneficial Effects

[0029] (1) The optical router of the present invention is used to realize programmable control of dichromatic photon momentum;

[0030] (2) The optical router of the present invention has the advantages of being light, thin and compact. By controlling the impact position of the electron beam, the green and red radiation directions can be dynamically regulated. The size of each pixel is controlled at the micrometer level. The high integration and small size expand its practical application range and contribute to the interdisciplinary research of on-chip spectroscopy, optical communication and integrated quantum information technology related applications.

[0031] (3) The optical router of the present invention overcomes the diffraction limit of light and realizes a subwavelength-scale electron-induced color router. Under the stimulation of the electron beam, the subwavelength displacement of the impact position can directly adjust the distribution of the localized state density of the gold nanoantenna electrons, thereby promoting the adjustable change of the far-field emission pattern.

[0032] (4) The optical router of the present invention has the advantages of high robustness and large capacity, and can be applied to high-dimensional, low-crosstalk optical information encoding and encryption. The optical router under electron beam excitation can be manipulated for frequency-dependent quaternary coding, and can also manipulate the momentum of two-color photons by moving the impact position on a deep subwavelength scale. The modulation dimension of information transmission is increased.

[0033] (5) The optical router of the present invention uses the momentum of two-color photons and the intensity of light beams as carriers, which improves the information processing capability and increases the information capacity based on frequency-related angle measurement. In addition, the unit-type spatial distribution characteristics can realize real-time image display. It can be used as an integrated and miniaturized display device in the field of virtual display and enhanced display.

[0034] (6) The optical router of the present invention is scalable. Materials with higher plasma q factors such as aluminum and silver can be introduced into the design of the optical router to achieve better display performance.

[0035] (7) The present invention relates to an optical router excited by an electron beam at a subwavelength scale and a method for preparing the same, which is used to modulate the momentum of two-color photons. When an electron beam from an on-chip source hits the edge of a gold nanoantenna, the green and red light components of the far-field emission are distributed along different propagation directions, while when the impact position is at the center, a non-split pattern is observed. In addition, the conversion of the characteristic radiation direction can be triggered by controlling the electron beam impact position. By rationally adjusting the excitation position and changing the far-field interference of the dipole and quadrupole moments, active modulation of two-color photon splitting can be effectively achieved. The present invention provides a convincing platform for manipulating photon momentum at the nanoscale, paving the way for future quantum information technology and integrated photonic systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a schematic diagram of an optical router in a specific embodiment of the present invention, in which the cross-shaped gold nanoantenna generates asymmetric dichroic dispersion radiation under electron beam excitation;

[0037] Figure 2 This is a pseudo-color scanning electron microscope image of a gold nanoantenna in a specific embodiment of the present invention, where the red dots indicate the electron beam excitation positions;

[0038] Figure 3 The experimental and simulated spectra of the gold nanoantenna in the specific embodiment of the present invention. The blue (black) curve corresponds to the experimental (simulated) spectrum;

[0039] Figure 4 is the scattering intensity of various multipole moments in the gold nanoantenna in the specific implementation mode of the present invention;

[0040] Figure 5 A near-field intensity diagram of a simulated red component in a specific embodiment of the present invention;

[0041] Figure 6 A near-field intensity diagram of a simulated green component in a specific embodiment of the present invention;

[0042] Figure 7 are the electron beam excitation positions in the specific implementation mode of the present invention. They are located at the upper left corner, upper right corner, lower edge center and center of the gold nanoantenna, respectively, and are marked with red dots on the pseudo-color scanning electron microscope image of the gold nanoantenna;

[0043] Figure 8 This is an experimental angular dichroic diagram generated by respectively exciting the upper left corner, upper right corner, lower edge center and center of the gold nanoantenna in a specific embodiment of the present invention. DETAILED DESCRIPTION

[0044] The present invention is further described in detail below through specific embodiments in conjunction with the accompanying drawings so that those skilled in the art can understand the present invention more clearly.

[0045] A color router for photon momentum manipulation to modulate the momentum of two-color photons, e.g. Figure 1 shown.

[0046] The color router is composed of a cross-shaped gold nanoantenna, a carbon nanotube film and a printed circuit board. The length and width of the cross-shaped gold nanoantenna range from 200nm to 600nm, 50nm to 100nm, and the thickness ranges from 50nm to 100nm. Figure 2As shown. Below the gold nanoantenna is an ultra-precision aligned carbon nanotube film. A printed circuit board is integrated below the carbon nanotube film. The electron beam excitation position is controlled by programming the programmable gate array, thereby controlling the radiation direction of the red and green light. Array-arranged excitation units are etched on the printed circuit board. Each excitation unit includes five emission cathodes and five gates. A programmable gate array is integrated under each emission cathode to achieve flexible adjustment and rapid response of the emission cathode. The programmable gate array is used to control the level shifter of each excitation unit. The programmable gate array uses vertical and horizontal scanning circuits. When the emission cathode excites different positions of the carbon nanotube film above it, the electrons on the carbon nanotube film are enriched and further emitted to the cross-shaped metal nanoantenna, achieving electron beam excitation with nanometer-level precision. Under electron beam excitation, the experimental and simulated spectra of radiation from the gold nanoantenna with a size of 400nm×70nm are shown in the figure below. Figure 3 shown.

[0047] The scattering intensity I of the color router when excited by an electron beam is:

[0048]

[0049] Among them, P, M, T, Q αβ 、M αβ and T αβ They correspond to electric dipole, magnetic dipole, circular dipole, electric quadrupole, magnetic quadrupole, and circular quadrupole, respectively. c is the speed of light in a vacuum, ω is the angular frequency, O represents the harmonic minimum term, and α and β are the horizontal and vertical coordinates of the orthogonal coordinate system. The scattering intensity of various multipole moments in a 400nm×70nm gold nanoantenna is shown in Figure 2. Figure 4 shown.

[0050] The printed circuit board in the color router can control the radiation direction of photons. When the electron beam on the printed circuit board hits the edge of the cross-shaped gold nanoantenna, the green and red components of the far-field emission are distributed along different propagation directions, where the red component is as follows: Figure 5 As shown, the green component is Figure 6 When an electron beam on a printed circuit board hits the center of a cross-shaped metal nanoantenna, the green and red components of the far-field emission are distributed along the same propagation direction, i.e., a non-split pattern is observed.

[0051] By adjusting the electron beam excitation position through the printed circuit board and changing the far-field interference of the dipole moment and the quadrupole moment, the active modulation of the two-color photon splitting can be effectively achieved. The five electron beam position excitation positions are located at the upper left corner, upper right corner, lower edge center and center of the gold nanoantenna, respectively. Figure 7 The corresponding experimental angular dichroic image of the cross-shaped gold nanoantenna is shown in Figure 8 shown.

[0052] The method for preparing a cross-shaped metal nanoantenna is:

[0053] In the first step, a metal layer is deposited on a substrate using an electron beam evaporator, and then a positive resist is spin-coated on the metal layer and etched using an electron beam lithography process to form a cross-shaped metal nanostructure.

[0054] In the second step, the cross-shaped metal nanostructure formed in the first step is irradiated with argon ions to remove the residual polymethyl methacrylate;

[0055] The third step is to immerse the cross-shaped metal nanostructure obtained in the second step in ethanol, clean it in the ethanol with ultrasound, and then dry it in an oven. After drying, a commercial polydimethylsiloxane solution is cast on the dried cross-shaped metal nanostructure, and finally degassed and cured in a vacuum oven to obtain a nanostructured polydimethylsiloxane film, and the nanostructured polydimethylsiloxane film is peeled off from the substrate to obtain a cross-shaped metal nanoantenna;

[0056] The substrate material is silicon dioxide or silicon;

[0057] The method of transferring the carbon nanotube film to the upper surface of the printed circuit board is:

[0058] Step 1, transferring the carbon nanotube film onto a substrate and forming a strip array by reactive ion etching;

[0059] Step 2, patterning the carbon nanotube film formed into a strip array in step 1 by electron beam lithography;

[0060] Step 3, performing electron beam evaporation deposition of substrate material on the pattern of step 2;

[0061] Step 4, peeling the carbon nanotube film obtained in step 3 off the substrate;

[0062] Step 5. In order to improve the alignment accuracy, electron beam lithography and electron beam evaporation are used to create marks on the carbon nanotube film peeled off in step 4, and then the marked carbon nanotube film is transferred to the printed circuit board. During the transfer, the substrate material deposited on the carbon nanotube film faces the printed circuit board. Finally, hydrofluoric acid is used to selectively etch the substrate material and the emission cathode under the carbon nanotube film.

[0063] The center position of the prepared cross-shaped metal nanoantenna is aligned with the created mark and transferred to the carbon nanotube film.

[0064] The present invention relates to an optical router excited by an electron beam at a subwavelength scale and a preparation method thereof, which are used to modulate the momentum of two-color photons. The color router is composed of a metal nanoantenna, a carbon nanotube film, and a printed circuit board. When the electron beam excites the edge of the metal nanoantenna, the green and red light components emitted in the far field are distributed along different propagation directions, while when the excitation position is located at the center, a non-split pattern is generated. In addition, the conversion of the characteristic radiation direction can be triggered by controlling the excitation position of the electron beam. By adjusting the excitation position and changing the far-field interference of the dipole moment and the quadrupole moment, active modulation of the splitting of two-color photons can be effectively achieved. The present invention provides a convincing platform for manipulating the momentum of photons at the nanoscale, paving the way for future quantum information technology and integrated photonic systems.

[0065] Finally, it should be noted that the purpose of publishing the embodiments is to help further understand the present invention. Those skilled in the art should understand that various substitutions and modifications are possible without departing from the spirit and scope of the present invention and the appended claims. Therefore, the present invention should not be limited to the contents disclosed in the embodiments, and the scope of protection claimed by the present invention shall be subject to the scope defined in the claims.

[0066] In summary, the above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A color router for photon momentum manipulation, characterized in that: The color router includes a cross-shaped metal nanoantenna, a carbon nanotube film, and a printed circuit board; The cross-shaped metal nanoantenna is formed by placing two rectangular metal nanoantennas perpendicular to each other, and the rectangular metal nanoantenna has a length of 200-600nm, a width of 50-100nm, and a thickness of 50-100nm; The cross-shaped metal nanoantenna is located on the upper surface of the carbon nanotube film; The carbon nanotube film is located on the upper surface of the printed circuit board.

2. A color router for photon momentum manipulation according to claim 1, characterized in that: The printed circuit board is etched with excitation units arranged in an array, each excitation unit includes five emission cathodes and five grids, and a programmable gate array is integrated under each emission cathode.

3. A color router for photon momentum manipulation according to claim 1, characterized in that: The programmable gate array is used to control the excitation position of the electron beam, thereby controlling the radiation direction of the red and green light; The programmable gate array uses vertical and horizontal scanning circuits; When the emission cathode excites different positions of the carbon nanotube film above it, the electrons on the carbon nanotube film are enriched and further emitted to the cross-shaped metal nanoantenna, achieving electron beam excitation with nanometer-level precision.

4. A color router for photon momentum manipulation according to claim 1, characterized in that: The metal is aluminum, gold or silver.

5. The color router for photon momentum manipulation according to claim 1, characterized in that: The scattering intensity I of the color router when excited by an electron beam is: Among them, P, M, T, Q αβ 、M αβ and T αβ They correspond to electric dipole, magnetic dipole, circular dipole, electric quadrupole, magnetic quadrupole, and circular quadrupole respectively. c is the speed of light in vacuum, ω is the angular frequency, O represents the harmonic minimum term, and α and β are the horizontal and vertical coordinates in the orthogonal coordinate system.

6. A color router for photon momentum manipulation according to claim 1, characterized in that: The printed circuit board can regulate the radiation direction of photons. When the electron beam on the printed circuit board hits the edge of the cross-shaped metal nanoantenna, the green and red components of the far-field emission are distributed along different propagation directions. When the electron beam on the printed circuit board hits the center of the cross-shaped metal nanoantenna, the green and red components of the far-field emission are distributed along the same propagation direction, that is, a non-split pattern is observed.

7. The color router for photon momentum manipulation according to claim 1, characterized in that: The method for preparing a cross-shaped metal nanoantenna is: In the first step, a metal layer is deposited on a substrate using an electron beam evaporator, and then a positive resist is spin-coated on the metal layer and etched using an electron beam lithography process to form a cross-shaped metal nanostructure. In the second step, the cross-shaped metal nanostructure formed in the first step is irradiated with argon ions to remove the residual polymethyl methacrylate; The third step is to immerse the cross-shaped metal nanostructure obtained in the second step in ethanol, clean it in the ethanol with ultrasound, and then dry it in an oven. After drying, a commercial polydimethylsiloxane solution is cast on the dried cross-shaped metal nanostructure, and finally degassed and cured in a vacuum oven to obtain a nanostructured polydimethylsiloxane film, and the nanostructured polydimethylsiloxane film is peeled off from the substrate to obtain a cross-shaped metal nanoantenna; The substrate material is silicon dioxide or silicon.

8. A color router for photon momentum manipulation according to claim 7, characterized in that: The method of transferring the carbon nanotube film to the upper surface of the printed circuit board is: Step 1, transferring the carbon nanotube film onto a substrate and forming a strip array by reactive ion etching; Step 2, patterning the carbon nanotube film formed into a strip array in step 1 by electron beam lithography; Step 3, performing electron beam evaporation deposition of substrate material on the pattern of step 2; Step 4, peeling the carbon nanotube film obtained in step 3 off the substrate; In step 5, electron beam lithography and electron beam evaporation are used to create marks on the carbon nanotube film peeled off in step 4, and the marked carbon nanotube film is then transferred to a printed circuit board with the substrate material deposited on the carbon nanotube film facing the printed circuit board. Finally, hydrofluoric acid is used to selectively etch the substrate material and the emission cathode under the carbon nanotube film.

9. A color router for photon momentum manipulation according to claim 8, characterized in that: The center position of the prepared cross-shaped metal nanoantenna is aligned with the created mark and transferred to the carbon nanotube film.

10. A method for preparing a color router for photon momentum manipulation, characterized in that: Step 11, depositing a metal layer on the substrate using an electron beam evaporator, then spin-coating a positive electrode resist on the metal layer, and etching using an electron beam lithography process to form a cross-shaped metal nanostructure; Step 12, irradiating the formed cross-shaped metal nanostructure with argon ions to remove residual polymethyl methacrylate; Step 13, immersing the obtained cross-shaped metal nanostructure in ethanol, cleaning it in the ethanol with ultrasound, and then drying it in an oven. After drying, casting a commercial polydimethylsiloxane solution on the dried cross-shaped metal nanostructure, and finally degassing and curing it in a vacuum oven to obtain a nanostructured polydimethylsiloxane film, and peeling the nanostructured polydimethylsiloxane film from the substrate to obtain a cross-shaped metal nanoantenna; Step 14, transferring the carbon nanotube film onto a substrate and forming a strip array by reactive ion etching, patterning the carbon nanotube film forming the strip array by electron beam lithography, and performing electron beam evaporation deposition of substrate material on the pattern; Step 15, peeling the obtained carbon nanotube film from the substrate, and using electron beam lithography and electron beam evaporation to create marks on the peeled carbon nanotube film, and then transferring the marked carbon nanotube film to a printed circuit board, with the substrate material deposited on the carbon nanotube film facing the printed circuit board during the transfer, and finally, selectively etching the substrate material and the emission cathode under the carbon nanotube film with hydrofluoric acid; Step 16, aligning the center position of the prepared cross-shaped metal nanoantenna with the created mark and transferring it to the carbon nanotube film to obtain a color router for photon momentum manipulation.

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