A photonic nanojet microcolumn array, a preparation method and an optical system
By designing a photonic nanojet array using high-refractive-index dielectric materials and micropillar structures, the problems of excessive beam width and processing difficulty were solved, achieving the technical effects of laser processing, super-resolution imaging, and single-molecule detection.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHANGCHUN INST OF OPTICS FINE MECHANICS & PHYSICS CHINESE ACAD OF SCI
- Filing Date
- 2022-12-07
- Publication Date
- 2026-06-12
AI Technical Summary
In existing photonic nanojet technology, the beam width is large when using low refractive index medium materials, while when using high refractive index materials, photonic nanojet will focus inside, and the small size of the micropillars makes processing and operation difficult.
Micropillar structures are designed using two or three refractive index media materials, including embedded triangular structures, notched structures, and ring structures. By utilizing the wave superposition effect of high refractive index media materials and the internal structure of the micropillar, the structural parameters are adjusted to achieve a resonant state and compress the beam width.
It achieves a beam width of less than 100 nanometers, reduces the difficulty of micropillar fabrication and use, improves the etching accuracy of laser processing and the imaging resolution of super-resolution imaging, and enhances single-molecule detection capabilities.
Smart Images
Figure CN116300125B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of optical technology, and in particular to a micropillar array of photon nanojet, its preparation method, and an optical system. Background Technology
[0002] The resolution of an optical microscope depends on the size of the spot produced by the incident light in the far field. At the end of the 19th century, German physicist Alexander Abbe pointed out that the resolution limit of an optical microscope is half the illumination wavelength. Photonic nanojet is a subwavelength, high-intensity, narrow beam of light produced when a light beam illuminates a microparticle (microsphere or micropillar) on its shadowed side, which can overcome the diffraction limit. Furthermore, due to its high-intensity super-resolution focusing properties, it can be applied to laser processing, super-resolution imaging, single-molecule detection, and other fields. The core parameters of photonic nanojet include beam width (also known as full width at half maximum, FWHM), peak intensity, and effective length. Among these, beam width is the most direct indicator of its ability to overcome diffraction.
[0003] In recent years, researchers have proposed a series of methods to shorten the beam width. However, due to the use of low-refractive-index materials, the beam width is mostly above 100 nanometers. Using high-refractive-index materials increases high-frequency components, resulting in narrower photon nanojet beams. However, when the refractive index contrast is greater than 2, the photon nanojet beams focus internally, making low-refractive-index micropillar structures unsuitable. New design methods are needed to solve this problem. Furthermore, due to the small size of micropillars, they are difficult to fabricate and manipulate, posing significant operational challenges in practical applications. Summary of the Invention
[0004] In view of this, this invention provides a micropillar array of photonic nanojet, a preparation method, and an optical system.
[0005] In a first aspect, the present invention provides a micropillar array for photon nanojet, comprising two refractive index medium materials, corresponding to a first refractive index medium material region and a second refractive index medium material region, respectively. The second refractive index medium material region consists of two embedded triangular structures, and the first refractive index medium material region has a notch structure corresponding to the two embedded triangular structures. The first refractive index medium material region and the second refractive index medium material region constitute a circular structure. The first refractive index of the first refractive index medium material region is less than 2, and the second refractive index of the second refractive index medium material region is greater than 2. An annular structure is provided around the circular structure, and the annular refractive index of the annular structure is the same as the second refractive index of the second refractive index medium material region. Parallel light incident from the first refractive index medium material region toward the second refractive index medium material region is used to generate photon nanojet.
[0006] As an optional scheme, the first refractive index n1 of the first refractive index medium material region is 1.43, the radius of the first refractive index medium material region is 6λ, the radius of the annular structure is 6.2λ, the annular refractive index n2 is 3.5, the lateral distance h of the notch structure from the center of the circle is 5.28λ, and the spacing w between the two embedded triangular structures is 0.2µm, where λ is a constant;
[0007] The parallel light has a wavelength of 565nm, propagates along the positive y-axis, and is incident with z-axis polarization. The external environment is air with a refractive index of 1. When the parallel light is incident, the photon nanojet has a transverse half-width of 66.7nm.
[0008] Secondly, this invention provides a micropillar array for photon nanojet, comprising three refractive index media materials, corresponding to a structural substrate, a first refractive index media material region, and a second refractive index media material region, respectively. The first refractive index media material region has a first step structure, a second step structure, a third step structure, a fourth step structure, and a fifth step structure. The two refractive index media material regions surround the first refractive index media material region, and a fixed interval is maintained between the first refractive index media material region and the second refractive index media material region. The first step structure is integrated with the structural substrate through the second refractive index media material region. The substrate refractive index, the first refractive index of the first refractive index media material region, and the second refractive index of the second refractive index media material region are all different. The side of the structural substrate facing away from the first refractive index media material region is the incident end. Parallel light is incident from the incident end to obtain two-photon nanojet with symmetrical sides.
[0009] As an optional scheme, the structure substrate has a width of 16 μm and a height of 50 μm. The refractive index n of the substrate is 1.46. The first refractive index n1 of the first refractive index medium material region is 1.43, and the second refractive index n2 of the second refractive index medium material region is 2.6479. The width w3 of the first step structure is 2 μm, the width w1 of the third step structure is 1.1 μm, the width of the fourth step structure is the same as that of the third step structure, the width w2 of the fifth step structure is 4 μm, the width of the second step structure is (w2-w3) / 2, the height h1 of the second step structure from the structure substrate is 0.3 μm, the height h2 of the third step structure from the structure substrate is 2.1 μm, the height h3 of the fourth step structure from the structure substrate is 4.6 μm, the height h4 of the fifth step structure from the structure substrate is 6.2 μm, the wavelength of the parallel light is 550 nm, and when the parallel light is incident, a two-photon nanojet with a full width at half maximum (FWHM) of 89 nm is symmetrically obtained on both sides.
[0010] As an optional scheme, the structure substrate has a width of 16 μm and a height of 50 μm. The refractive index n of the substrate is 1.46. The first refractive index n1 of the first refractive index medium material region is 1.43, and the second refractive index n2 of the second refractive index medium material region is 2.6479. The width w3 of the first step structure is 2 μm, the width w1 of the third step structure is 1.1 μm, the width of the fourth step structure is the same as that of the third step structure, the width w2 of the fifth step structure is 4 μm, the width of the second step structure is (w2-w3) / 2, the height h1 of the second step structure from the structure substrate is 0.3 μm, the height h2 of the third step structure from the structure substrate is 2.1 μm, the height h3 of the fourth step structure from the structure substrate is 4.3 μm, the height h4 of the fifth step structure from the structure substrate is 6.2 μm, the wavelength of the parallel light is 550 nm, and when the parallel light is incident, three-photon nanojet with a full width at half maximum (FWHM) of 120 nm is obtained symmetrically on the left and right sides.
[0011] Thirdly, this invention provides a method for preparing a micropillar array of photon nanojet, used to prepare a micropillar array of photon nanojet as described above.
[0012] Fourthly, the present invention provides an optical system comprising a micropillar array having photon nanojet patterns as described above.
[0013] This invention provides a micropillar array for photonic nanojetting, its fabrication method, and an optical system. Utilizing the wave superposition effect of a high-refractive-index medium and the internal structure of the micropillars, the beam width is further compressed. When a certain structural parameter within the micropillar is changed to achieve resonance, the beam width reaches a minimum; the closer to the resonance state, the narrower the beam width. Changing the internal structure of the micropillar allows for beam emission. Furthermore, for ease of fabrication and use, the photonic nanojetting micropillar array can generate dual-beam nanojet streams with beam widths below 100 nanometers, reducing fabrication and application difficulty. These structures can be used in laser processing to improve etching precision, super-resolution imaging to improve imaging resolution, and single-molecule detection, among other fields. Attached Figure Description
[0014] Figure 1 This is a schematic diagram of a micropillar array for photon nanojetting provided in an embodiment of the present invention;
[0015] Figure 2 This invention provides a FWHM curve of the micropillar surface of a photon nanojet micropillar array.
[0016] Figure 3 This is a graph showing the variation of the photon nanojet FWHM curve of a micro-column array for photon nanojet in an embodiment of the present invention;
[0017] Figure 4 This is a schematic diagram of the connection between a micro-column array for photon nanojetting and an optical system provided in an embodiment of the present invention;
[0018] Figure 5 This is a schematic diagram of a micro-column array for photon nano-jetting provided in an embodiment of the present invention;
[0019] Figure 6 This is a schematic diagram of the electric field distribution of a micro-column array for photon nano-jetting provided in an embodiment of the present invention;
[0020] Figure 7 This is a schematic diagram of the single-field distribution of a micro-column array of photon nanojet generators provided in an embodiment of the present invention;
[0021] Figure 8 This invention provides a micro-column array and optical system structure array diagram for photon nano-jetting in an embodiment of the present invention. Detailed Implementation
[0022] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.
[0023] The terms "first," "second," "third," "fourth," etc., used in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.
[0024] Combination Figure 1As shown, this invention provides a micropillar array for photon nanojet, comprising two refractive index media materials, corresponding to a first refractive index media material region 1 and a second refractive index media material region 2, respectively. The second refractive index media material region 2 consists of two embedded triangular structures. The first refractive index media material region 1 has a notch structure corresponding to the two embedded triangular structures. The first refractive index media material region 1 and the second refractive index media material region 2 form a circular structure. The first refractive index of the first refractive index media material region 1 is less than 2, and the second refractive index of the second refractive index media material region 2 is greater than 2. An annular structure 3 is provided around the circular structure. The annular refractive index of the annular structure 3 is the same as the second refractive index of the second refractive index media material region 2. Parallel light incident from the first refractive index media material region 1 toward the second refractive index media material region 2 results in a photon nanojet.
[0025] As an optional scheme, the first refractive index n1 of the first refractive index medium material region 1 is 1.43, the radius of the first refractive index medium material region 1 is 6λ, the radius of the annular structure 3 is 6.2λ, the annular refractive index n2 is 3.5, the lateral distance h of the notch structure from the center of the circle is 5.28λ, and the spacing w between the two embedded triangular structures is 0.2µm, where λ is a constant;
[0026] Combination Figure 2 As shown, the wavelength of the parallel light is 565nm, it propagates along the positive y-axis and is incident with z-axis polarization, the external environment is air, the refractive index is 1, and the horizontal half-width is 66.7nm when the parallel light is incident.
[0027] Combination Figure 3 As shown in the figure, the FWHM curve variation diagram of photonic nanojet reveals a rule for shortening the beam width: when the structural parameter h is adjusted, the beam width has a minimum value when the structure is in resonance (asterisk in the figure); the closer to resonance, the smaller the beam width.
[0028] Combination Figure 4 As shown in the diagram, the micropillar array of photonic nanojet provided by this invention is connected to an optical system. The divergent light beam is focused into parallel light by a lens and then irradiates the structure of the micropillar array of photonic nanojet.
[0029] Combination Figure 5As shown, this invention provides a micropillar array for photon nanojet, comprising three refractive index media materials, corresponding to a structural substrate 10, a first refractive index media material region 11, and a second refractive index media material region 22, respectively. The first refractive index media material region 11 has a first step structure 111, a second step structure 112, a third step structure 113, a fourth step structure 114, and a fifth step structure 115. The two refractive index media material regions 22 surround the first refractive index media material region 11, and a fixed interval is maintained between the first refractive index media material region 11 and the second refractive index media material region 22. The first step structure 111 is integrated with the structural substrate 10 through the second refractive index media material region 22. The base refractive index of the structural substrate 10, the first refractive index of the first refractive index media material region 11, and the second refractive index of the second refractive index media material region 22 are all different. The side of the structural substrate 10 facing away from the first refractive index media material region 11 is the incident end. Parallel light is incident from the incident end to obtain two-photon nanojet with symmetrical sides.
[0030] Combination Figure 5 and Figure 6 As shown, in one embodiment, the structural substrate 10 has a width of 16 μm and a height of 50 μm. The refractive index n of the substrate is 1.46. The first refractive index n1 of the first refractive index medium material region 11 is 1.43, the second refractive index n2 of the second refractive index medium material region 22 is 2.6479, the width w3 of the first step structure 111 is 2 μm, the width w1 of the third step structure 113 is 1.1 μm, the width of the fourth step structure 114 is the same as the width of the third step structure 113, and the width w2 of the fifth step structure 115 is 4 μm. The width of the second step structure is (w2-w3) / 2, the height h1 of the second step structure from the structural substrate is 0.3 μm, the height h2 of the third step structure 113 from the structural substrate 10 is 2.1 μm, the height h3 of the fourth step structure 114 from the structural substrate is 4.6 μm, the height h4 of the fifth step structure 115 from the structural substrate 10 is 6.2 μm, the wavelength of the parallel light is 550 nm, and when the parallel light is incident, a two-photon nanojet with a full width at half maximum (FWHM) of 89 nm is symmetrically obtained on both sides. Figure 6 This is an electric field distribution diagram, where the structural parameters are as follows: Figure 5 As marked.
[0031] Combination Figure 7As shown, in one embodiment, the intensity and number of emitted beams can be controlled by changing the height h3 and refractive index n1. In this embodiment, a three-photon nanojet is output. The height h3 of the fourth step structure 114 from the structural substrate is adjusted to 4.3 μm. The remaining parameters are consistent with the previous embodiment. The width of the structural substrate 10 is 16 μm, the height is 50 μm, the refractive index n of the substrate is 1.46, the first refractive index n1 of the first refractive index medium material region 111 is 1.43, the second refractive index n2 of the second refractive index medium material region 112 is 2.6479, the width w3 of the first step structure 111 is 2 μm, the width w1 of the third step structure 113 is 1.1 μm, and the fourth step structure... The width of structure 114 is the same as the width of the third step structure 113. The width w2 of the fifth step structure 115 is 4 μm. The width of the second step structure 112 is (w2-w3) / 2. The height h1 of the second step structure 112 from the structural substrate is 0.3 μm. The height h2 of the third step structure 113 from the structural substrate 10 is 2.1 μm. The height h3 of the fourth step structure 114 from the structural substrate 10 is 4.3 μm. The height h4 of the fifth step structure 115 from the structural substrate 10 is 6.2 μm. The wavelength of the parallel light is 550 nm. When the parallel light is incident, three-photon nanojet with a full width at half maximum (FWHM) of 120 nm is obtained symmetrically on the left and right sides.
[0032] Combination Figure 8 As shown in the schematic diagram of the assembly of the photon nanojet micropillar array in this embodiment of the invention, three sets are arranged in parallel. The divergent light beam is focused into parallel light by a lens and then irradiates the structure of the photon nanojet micropillar array.
[0033] This invention provides a micropillar array for photonic nanojetting. Utilizing the wave superposition effect of a high-refractive-index medium and the internal structure of the micropillars, the beam width is further compressed. When a certain structural parameter within the micropillar is changed to achieve resonance, the beam width reaches a minimum; the closer to the resonance state, the narrower the beam width. Changing the internal structure of the micropillars allows for beam emission. Furthermore, for ease of fabrication and use, the photonic nanojetting micropillar array can generate dual-beam nanojet streams with beam widths below 100 nanometers, reducing fabrication and application difficulty. These structures can be used in fields such as laser processing to improve etching precision, super-resolution imaging to improve imaging resolution, and single-molecule detection.
[0034] Accordingly, this invention provides a method for preparing a micropillar array of photon nanojet, used to prepare the micropillar array of photon nanojet as described above.
[0035] This invention provides a method for fabricating a micropillar array of photonic nanojet, which achieves a highly localized light field, compresses the lateral scale to 66.7 nm, and increases the light intensity to more than fifty times that of the incident light. This greatly reduces the difficulties in fabricating and operating the micropillars, and the incident light field only needs to be parallel light, avoiding complex optical systems. It can be used in laser processing, super-resolution imaging, and single-molecule detection.
[0036] Accordingly, an optical system is provided in this invention, comprising a micropillar array having photon nanojet as described above.
[0037] The optical system provided by this invention can be used in fields such as laser processing to improve etching accuracy, super-resolution imaging to improve imaging resolution, and single-molecule detection.
[0038] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.
Claims
1. A micropillar array of photonic nanojet generators, characterized in that, It includes two refractive index medium materials, corresponding to a first refractive index medium material region and a second refractive index medium material region, respectively. The second refractive index medium material region consists of two embedded triangular structures. The first refractive index medium material region has a notch structure corresponding to the two embedded triangular structures. The first refractive index medium material region and the second refractive index medium material region form a circular structure. A ring structure is provided around the circular structure. The ring refractive index of the ring structure is the same as the second refractive index of the second refractive index medium material region. When parallel light is incident from the first refractive index medium material region toward the second refractive index medium material region, photon nano-jet is obtained. The beam width is compressed by the wave superposition effect of the high refractive index medium material and the internal structure of the micropillar. The first refractive index of the first refractive index medium material region is n1=1.43, the radius of the first refractive index medium material region is 6λ, the radius of the annular structure is 6.2λ, the annular refractive index is n2=3.5, the lateral distance h of the notch structure from the center of the circle is 5.28λ, and the spacing w between the two embedded triangular structures is 0.2um, where λ is a constant; The parallel light has a wavelength of 565nm, propagates along the positive y-axis, and is incident with z-axis polarization. The external environment is air with a refractive index of 1. When the parallel light is incident, the photon nanojet has a transverse half-width of 66.7nm.
2. A micropillar array of photonic nanojet, characterized in that, It includes three refractive index medium materials, corresponding to the structural substrate, the first refractive index medium material region, and the second refractive index medium material region, respectively. The first refractive index medium material region has a first step structure, a second step structure, a third step structure, a fourth step structure, and a fifth step structure. The second refractive index medium material region surrounds the first refractive index medium material region, and a fixed interval is maintained between the first refractive index medium material region and the second refractive index medium material region. The first step structure is integrated with the structural substrate through the second refractive index medium material region. The base refractive index of the structural substrate, the first refractive index of the first refractive index medium material region, and the second refractive index of the second refractive index medium material region are all different. The side of the structural substrate away from the first refractive index medium material region is the incident end. Parallel light is incident from the incident end and symmetrical two-photon nanojet is obtained on both sides. The beam width is compressed by the wave superposition effect of the high refractive index medium material and the internal structure of the micropillar.
3. The micropillar array of photonic nanojet according to claim 2, characterized in that, The substrate has a width of 16 μm and a height of 50 μm. The refractive index n of the substrate is 1.
46. The first refractive index n1 of the first refractive index medium material region is 1.43, and the second refractive index n2 of the second refractive index medium material region is 2.6479. The width w3 of the first step structure is 2 μm, the width w1 of the third step structure is 1.1 μm, the width of the fourth step structure is the same as that of the third step structure, the width w2 of the fifth step structure is 4 μm, the width of the second step structure is (w2-w3) / 2, the height h1 of the second step structure from the substrate is 0.3 μm, the height h2 of the third step structure from the substrate is 2.1 μm, the height h3 of the fourth step structure from the substrate is 4.6 μm, and the height h4 of the fifth step structure from the substrate is 6.2 μm. The wavelength of the parallel light is 550 nm. When the parallel light is incident, a two-photon nanojet with a full width at half maximum (FWHM) of 89 nm is symmetrically obtained on both sides.
4. The micropillar array of photonic nanojet according to claim 2, characterized in that, The substrate has a width of 16 μm and a height of 50 μm. The refractive index n of the substrate is 1.
46. The first refractive index n1 of the first refractive index medium material region is 1.43, and the second refractive index n2 of the second refractive index medium material region is 2.6479. The width w3 of the first step structure is 2 μm, the width w1 of the third step structure is 1.1 μm, the width of the fourth step structure is the same as that of the third step structure, the width w2 of the fifth step structure is 4 μm, the width of the second step structure is (w2-w3) / 2, the height h1 of the second step structure from the substrate is 0.3 μm, the height h2 of the third step structure from the substrate is 2.1 μm, the height h3 of the fourth step structure from the substrate is 4.3 μm, and the height h4 of the fifth step structure from the substrate is 6.2 μm. The wavelength of the parallel light is 550 nm. When the parallel light is incident, three-photon nanojet with a full width at half maximum (FWHM) of 120 nm is obtained symmetrically on both sides.
5. A method for fabricating a micropillar array of photonic nanojet generators, characterized in that, Used to prepare micropillar arrays of photon nanojet as described in any one of claims 1 to 3.
6. An optical system, characterized in that, Includes a micropillar array having photon nanojet as described in any one of claims 1 to 3.