A distributed Bragg mirror resonator based on plasmonic supramolecular

Abstract

The present invention discloses a distributed Bragg reflector resonant cavity based on plasmonic supramolecular structures, comprising a plasmonic supramolecular distributed Bragg reflector and a dielectric cavity. The plasmonic supramolecular distributed Bragg reflector comprises a gold nanoparticle supramolecular array layer and a dielectric layer as repeating units, with the number of repeating units ranging from 1 to 100. The gold nanostructured supramolecular unit is composed of N densely packed gold nanoparticles. The distributed Bragg reflector resonant cavity is a sandwich structure consisting of two plasmonic supramolecular distributed Bragg reflectors and a dielectric cavity. The resonant cavity exhibits excellent properties such as a short cavity length, a high quality factor, and a deep resonance depth. Therefore, this distributed Bragg reflector resonant cavity with a plasmonic supramolecular array can effectively improve the performance of optoelectronic devices while reducing their size.

Description

Technical Field

[0001] The present invention relates to the field of optoelectronic devices, and in particular to a distributed Bragg reflector resonant cavity based on plasmon supramolecules. Background Art

[0002] A distributed Bragg reflector (DBR) consists of alternating layers of high-refractive-index material and low-refractive-index material, with each layer being an odd multiple of a quarter of the optical wavelength. Reflection occurs at the interface between the two dissimilar materials, and the reflection at the interface is in phase. Therefore, theoretically, by stacking a certain number of layers, a reflectivity of over 99% can be achieved. One type of DBR is based on dielectric materials, primarily oxides, nitrides, and fluorides. These materials are combined to form a Bragg reflector, and the refractive index difference can be relatively large. Therefore, a dielectric Bragg reflector only requires a dozen or so pairs of high- and low-refractive-index materials to achieve a reflection of over 99%, with a high-reflection bandwidth of approximately 100 nm. However, dielectric Bragg reflectors are often accompanied by certain absorption and scattering losses.

[0003] The other type is a distributed Bragg reflector based on semiconductor materials, mainly including III-V semiconductor material systems such as InP, GaAs, and GaN. In these material systems, because the growth technology is limited by lattice matching, two lattice-matched materials with different band gaps (different refractive indices) must be selected to form the Bragg reflector. The refractive index difference between the high and low refractive index materials of the Bragg reflector based on semiconductor materials is small, usually Δn / n<15%. Therefore, more pairs (20-80) need to be stacked to achieve high reflection, and the high reflection bandwidth is narrow. In addition, the more stacked layers, the higher the process requirements.

[0004] Due to the limited refractive index of these materials, achieving high reflectivity requires a relatively thick mirror, typically several to ten microns thick. Furthermore, the high-reflectivity bandwidth of these mirrors is relatively narrow, reducing the process tolerance for device fabrication. The resonant cavity formed using these Bragg reflectors has a relatively long total length, which is detrimental to device miniaturization. Summary of the Invention

[0005] Technical problem: The purpose of the present invention is to provide a distributed Bragg reflector resonant cavity based on plasmon supramolecules to solve the problems that the distributed Bragg reflectors made of traditional materials are thick and the resonant cavity based on traditional material reflectors is too large, which is not conducive to device miniaturization.

[0006] Technical solution: The present invention relates to a distributed Bragg reflector resonant cavity based on plasmon supramolecular, comprising: a plasmon supramolecular distributed Bragg reflector and a dielectric cavity, wherein the plasmon supramolecular distributed Bragg reflector comprises a gold nanoparticle supramolecular array layer and a dielectric layer as repeating units, the number of repeating units being 1 to 100, the gold nanoparticle supramolecular array layer being an array structure in which gold nanostructure supramolecular units are arranged in a tetragonal lattice or a hexagonal lattice, and the gold nanostructure supramolecular unit being composed of N gold nanoparticles densely arranged, where N is an integer ranging from 1 to 10. 12 The distributed Bragg reflector resonant cavity is a sandwich structure consisting of two plasmon supramolecular distributed Bragg reflectors and a dielectric cavity.

[0007] In the plasmon supramolecular distributed Bragg reflector, the gold nanoparticle supramolecular array layer has an array period greater than 20 nm; the spacing between the gold nanostructure supramolecular units is 1-10 6 nm.

[0008] The shape of the gold nanostructure supramolecular unit includes circle, quadrangle, hexagon or octagon.

[0009] The gold nanoparticles in the gold nanostructure supramolecular unit can be replaced by silver nanoparticles.

[0010] The gap between the gold nanoparticles is 1-10 nm.

[0011] The gold nanoparticles in the gold nanostructure supramolecular unit have shapes including sphere, cylinder, cube or regular octahedron; and the size of the gold nanoparticles is 20-100 nm.

[0012] The real part of the effective refractive index of the gold nanoparticle supramolecular array layer in the infrared band is greater than 4, and the imaginary part of the effective refractive index tends to 0.

[0013] The dielectric cavity includes an active dielectric cavity and a passive dielectric cavity.

[0014] The length of the dielectric cavity corresponding to the fundamental mode resonance mode in the distributed Bragg reflector resonant cavity is 1-3 μm; the resonance mode is located in the infrared band and has a deep resonance depth.

[0015] The upper and lower Bragg reflectors of the distributed Bragg reflector resonant cavity are both composed of two repeating units, and the total length of the resonant cavity is 2-5 μm.

[0016] Beneficial effects: Compared with the existing technology, the present invention has the following advantages:

[0017] 1. A plasmonic supramolecular distributed Bragg reflector is proposed, employing a high-effective-refractive-index gold nanoparticle supramolecular array layer and a low-refractive-index dielectric layer as the repeating unit layer. Compared to Bragg reflectors made of traditional materials, this Bragg reflector, composed of a gold nanoparticle supramolecular array layer and a dielectric layer, exhibits a large refractive-index contrast. This allows for high reflection with a wide bandwidth by stacking fewer layers, providing a new strategy for miniaturized and tunable devices.

[0018] 2. A distributed Bragg reflector resonant cavity based on plasmonic supramolecular structures is proposed. Due to the high reflectivity of the gold nanoparticle supramolecular array layer / dielectric layer reflector, a distributed Bragg reflector with a few layers of plasmonic supramolecular structures can easily form a resonant cavity with a short cavity length and a deep resonance depth. This distributed Bragg reflector resonant cavity based on plasmonic supramolecular structures can be used in optoelectronic devices to effectively reduce the size of the device while improving its performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of a distributed Bragg reflector resonant cavity based on plasmon supramolecules of the present invention.

[0020] The figure shows: a plasmonic supramolecular distributed Bragg reflector 100 , a repeating unit 10 , a dielectric layer 11 , a gold nanoparticle supramolecular array layer 12 , a gold nanostructure supramolecular unit 121 , and a dielectric cavity 200 . DETAILED DESCRIPTION

[0021] The technical solution of the present invention is further described below in conjunction with the accompanying drawings.

[0022] See also Figure 1 The present invention provides a distributed Bragg reflector resonant cavity based on plasmon supramolecular molecules, comprising a plasmon supramolecular distributed Bragg reflector and a dielectric cavity. The plasmon supramolecular distributed Bragg reflector comprises a gold nanoparticle supramolecular array layer 12 and a dielectric layer 11 as a repeating unit 10, the number of repeating units being 1 to 100. The gold nanoparticle supramolecular array layer is an array structure in which gold nanostructure supramolecular units are arranged at a certain distance in a tetragonal lattice or a hexagonal lattice. The gold nanostructure supramolecular unit is composed of N gold nanoparticles densely arranged, where N is an integer ranging from 1 to 10. 12 The resonant cavity is a sandwich structure consisting of two plasmon supramolecular distributed Bragg reflectors 100 and a dielectric cavity 200.

[0023] The technical solution provided by the embodiment of the present invention uses a gold nanoparticle supramolecular array layer with a high effective refractive index and a low refractive index dielectric layer as the repeating unit layer of the Bragg reflector. Compared with Bragg reflectors made of traditional materials, the Bragg reflector composed of this gold nanoparticle supramolecular array layer and the dielectric layer has a large refractive index difference. By stacking fewer layers, higher reflection and a large high reflection bandwidth can be achieved, which provides a new strategy for miniaturization and tunable devices. Due to its high reflective properties, a few-layer plasmonic nanostructure patterned supramolecular array distributed Bragg reflector can easily form a resonant cavity with a short cavity length and deep resonance depth. This distributed Bragg reflector resonant cavity based on plasmonic supramolecular molecules can be used in optoelectronic devices to effectively reduce the size of the device while improving its performance.

[0024] In an embodiment, the period of the supramolecular unit array is greater than 20 nm.

[0025] In the embodiment, the spacing between supramolecular units is 1-10 6 nm.

[0026] In an embodiment, the shape of the supramolecular unit includes circle, quadrilateral, hexagon or octagon.

[0027] In an embodiment, the gold in the gold nanoparticles can be replaced by silver or aluminum.

[0028] In the embodiment, the gold nanoparticles have a particle shape including sphere, cylinder, cube or regular octahedron.

[0029] In the embodiment, the size of the gold nanoparticles is 20-100 nm.

[0030] In the embodiment, the gap between the gold nanoparticles is 1-10 nm.

[0031] In an embodiment, the effective refractive index of the gold nanoparticle supramolecular array layer in the infrared band is greater than 4.

[0032] In the embodiment, the loss of the gold nanoparticle supramolecular array layer in the infrared band approaches zero.

[0033] In an embodiment, the novel resonant cavity includes the aforementioned plasmonic supramolecular distributed Bragg reflector.

[0034] In the embodiment, the dielectric cavity in the novel resonant cavity includes an active dielectric cavity and a passive dielectric cavity.

[0035] In the embodiment, the length of the dielectric cavity corresponding to the first-order resonance mode in the novel resonant cavity is 1-3 μm.

[0036] In the embodiment, the resonance mode of the resonant cavity is located in the infrared band and has a deep resonance depth.

[0037] In the embodiment, the upper and lower Bragg reflectors of the novel resonant cavity are both composed of two unit layers, and the total length of the resonant cavity is 2-5 μm.

Claims

1. A distributed Bragg reflector resonant cavity based on plasmon supramolecules, characterized in that: include: A plasmon supramolecular distributed Bragg reflector (100) and a dielectric cavity (200) are provided. The plasmon supramolecular distributed Bragg reflector (100) comprises a gold nanoparticle supramolecular array layer (12) and a dielectric layer (11) as repeating units (10), the number of repeating units (10) being 1 to 100. The gold nanoparticle supramolecular array layer (12) is an array structure in which gold nanostructure supramolecular units (121) are arranged in a tetragonal lattice or a hexagonal lattice. The gold nanostructure supramolecular unit is composed of N gold nanoparticles densely arranged, where N is an integer ranging from 1 to 10. 12 The distributed Bragg reflector resonant cavity is a sandwich structure consisting of two plasmon supramolecular distributed Bragg reflectors (100) and a dielectric cavity (200).

2. The distributed Bragg reflector resonant cavity based on plasmon supramolecules according to claim 1, characterized in that: In the plasmon supramolecular distributed Bragg reflector (100), the array period of the gold nanoparticle supramolecular array layer (12) is greater than 20 nm; the spacing between the gold nanostructure supramolecular units (121) is 1-10 6 nm.

3. The distributed Bragg reflector resonant cavity based on plasmon supramolecules according to claim 2, characterized in that: The shape of the gold nanostructure supramolecular unit (121) includes a circle, a quadrilateral, a hexagon or an octagon.

4. The distributed Bragg reflector resonant cavity based on plasmon supramolecules according to claim 3, characterized in that: The gold nanoparticles in the gold nanostructure supramolecular unit (121) can be replaced by silver nanoparticles.

5. The distributed Bragg reflector resonant cavity based on plasmon supramolecules according to claim 1, characterized in that: The gap between the gold nanoparticles is 1-10 nm.

6. The distributed Bragg reflector resonant cavity based on plasmon supramolecules according to claim 4, characterized in that: The gold nanoparticles in the gold nanostructure supramolecular unit (121) have shapes including sphere, cylinder, cube or regular octahedron; and the size of the gold nanoparticles is 20-100 nm.

7. The distributed Bragg reflector resonant cavity based on plasmon supramolecules according to claim 1, characterized in that: The real part of the effective refractive index of the gold nanoparticle supramolecular array layer (12) in the infrared band is greater than 4, and the imaginary part of the effective refractive index tends to 0.

8. The distributed Bragg reflector resonant cavity based on plasmon supramolecules according to claim 1, characterized in that: The dielectric cavity (200) comprises an active dielectric cavity and a passive dielectric cavity.

9. The distributed Bragg reflector resonant cavity based on plasmon supramolecules according to claim 1, characterized in that: The length of the dielectric cavity corresponding to the fundamental mode resonance mode in the distributed Bragg reflector resonant cavity is 1-3 μm; the resonance mode is located in the infrared band and has a deep resonance depth.

10. The distributed Bragg reflector resonant cavity based on plasmon supramolecules according to claim 1, characterized in that: The upper and lower Bragg reflectors of the distributed Bragg reflector resonant cavity are both composed of two repeating units (10), and the total length of the resonant cavity is 2-5 μm.

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