A resonator with ultra-high quality factor insensitive to incident angle
By incorporating bound states (BICs) into a dielectric AlGaAs cylindrical resonator, the problems of easy oxidation and high loss in metallic metamaterial resonators are solved, realizing an ultra-high quality factor resonator that is insensitive to the incident angle, thus enhancing the stability and performance of the second harmonic.
Patent Information
- Application Number
- CN202310414616.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-04-18
- Publication Date
- 2026-01-02
- Estimated Expiration
- 2043-04-18
AI Technical Summary
Existing high-quality factor metallic metamaterial resonators are prone to oxidation, have high losses, and have complex structures. Changes in the incident angle lead to unstable performance.
A periodically arranged dielectric AlGaAs pillar resonator is used. By merging bound states (BICs) at the center of the Brillouin zone, a resonance peak with an ultra-high quality factor is excited. The dispersion relation is designed to make the resonator insensitive to the incident angle.
It achieves an ultra-high quality factor unaffected by the incident angle, reduces losses, has a simple structure, high stability, and can achieve stable enhancement of the second harmonic.
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Figure CN116466420B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of resonators, and in particular to a resonator with super-high quality factor which is insensitive to incident angle. BACKGROUND
[0002] High quality factor (Q) optical resonators are essential for enhancing light-matter interaction in engineered photonic structures, but their performance is often affected by scattering losses due to fabrication imperfections. The confinement of electromagnetic waves in photonic crystal cavities and metamaterial resonators leads to new physical phenomena and high-performance optical devices. Bound states in the continuum (BICs) are waves that remain localized, coexisting with continuous radiative waves that can carry away energy. Although BICs were originally proposed in quantum mechanics, they are a universal wave phenomenon and have been observed in electromagnetic waves, sound waves in air, water waves, and elastic waves in solids. Ideal BICs have an infinitely high quality factor, and in fact, for a real device (a structure of finite size), all possible ideal BICs become leaky mode modes with high Q factors, also known as quasi-BIC modes.
[0003] In the 19th issue of Nature, volume 574, issue 24, it is proposed that by merging bound states in the continuum (BICs), the Q value of quasi-BICs can be significantly improved, providing a unique physical mechanism to overcome the scattering loss caused by defects. This discovery provides a new approach for the design of resonators with super-high quality factors. In summary, by merging several BICs, this paper proposes a quasi-BIC based on high dielectric constant dielectric column excitation to obtain an incident angle-insensitive local resonance with super-high quality factor. Therefore, we propose a resonator with super-high quality factor which is insensitive to incident angle to solve the above problems. SUMMARY
[0004] The resonator with super-high quality factor which is insensitive to incident angle proposed in the present application solves the problems in the background art.
[0005] In order to achieve the above-mentioned purpose, the present application adopts the following technical solutions:
[0006] A resonator with super-high quality factor which is insensitive to incident angle, comprising: the resonator is composed of a plurality of units arranged periodically, each unit has the same structure and is composed of a dielectric column composed of a dielectric AlGaAs.
[0007] As a preferred technical solution of the present application, the cross section of the resonator unit cell is a square.
[0008] As a preferred technical scheme of the present application, the resonator period is 1080-1100 nm, the medium column height is 845-855 nm, and the medium column radius is 265 nm.
[0009] As a preferred technical scheme of the present application, the resonator can move the accidental BIC in the momentum space to the center of the Brillouin zone by changing the period constant a, and combine the protected BIC together, to excite a resonant peak with an ultra-high quality factor, and the quality factor is proportional to the negative sixth power of the wave vector.
[0010] The present application has the following beneficial effects:
[0011] The present application aims to provide an angle-insensitive metamaterial resonator with an ultra-high quality factor, which solves the problems of metal oxidation, high loss and complex structure in the prior art high-quality-factor metal metamaterial resonator, and can produce an ultra-high Q local resonance that is not affected by the incident angle by using a simple medium column.
[0012] Compared with the metal metamaterial resonator with a high quality factor, the all-dielectric metamaterial resonator can achieve a higher quality factor and has a simple structure, and does not need to be stacked with multiple layers of metamaterials, is not sensitive to the incident angle, and has high stability.
[0013] The present application solves the problems of high loss and complex structure in the prior art high-quality-factor metal metamaterial resonator, and through the design of the dispersion relation, the working wavelength is shifted by a very small amount at different incident angles, and the resonant peak with an ultra-high quality factor can achieve a great enhancement of nonlinear response. BRIEF DESCRIPTION OF DRAWINGS
[0014] Figure 1 is a three-dimensional view of an angle-insensitive metamaterial resonator unit with an ultra-high quality factor according to the present application;
[0015] Figure 2 is a transmission spectrum diagram of an angle-insensitive metamaterial resonator with an ultra-high quality factor according to the present application in the working frequency band;
[0016] Figure 3 is an efficiency diagram of an angle-insensitive metamaterial resonator with an ultra-high quality factor according to the present application in the incident angle 4° for enhancing the second harmonic.
[0017] Figure 4 is an efficiency diagram of an angle-insensitive metamaterial resonator with an ultra-high quality factor according to the present application in the incident angle 8° for enhancing the second harmonic.
[0018] Figure 5 is a diagram showing the efficiency of the second harmonic enhancement of the angle-insensitive metamaterial resonator with ultra-high quality factor of the present application at an incident angle of 12°. DETAILED DESCRIPTION
[0019] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments.
[0020] Embodiment one
[0021] Referring to Figure 1 An angle-insensitive resonator with ultra-high quality factor, which is composed of a plurality of units arranged periodically, each of the units has the same structure and is composed of a dielectric column composed of a dielectric AlGaAs, the cross section of the resonator unit cell is square, the resonator period is 1080 nm, the height of the dielectric column is 845 nm, and the radius of the dielectric column is 265 nm.
[0022] Embodiment two
[0023] Referring to Figure 1 An angle-insensitive resonator with ultra-high quality factor, which is composed of a plurality of units arranged periodically, each of the units has the same structure and is composed of a dielectric column composed of a dielectric AlGaAs, the cross section of the resonator unit cell is square, the resonator period is 1090 nm, the height of the dielectric column is 850 nm, and the radius of the dielectric column is 265 nm.
[0024] Embodiment three
[0025] Referring to Figure 1 An angle-insensitive resonator with ultra-high quality factor, which is composed of a plurality of units arranged periodically, each of the units has the same structure and is composed of a dielectric column composed of a dielectric AlGaAs, the cross section of the resonator unit cell is square, the resonator period is 1100 nm, the height of the dielectric column is 855 nm, and the radius of the dielectric column is 265 nm.
[0026] The resonator can move the accidental BIC in the momentum space to the center of the Brillouin zone and combine it with the protected BIC by changing the period constant a, so as to excite a resonant peak with ultra-high quality factor, and the quality factor is proportional to the sixth power of the negative wave vector.
[0027] As shown in the accompanying Figure 2The transmission spectrum corresponding to different incident angles under a certain parameter combination is given, and it can be seen that three resonance peaks can be obtained, in addition to the perfect BIC at normal incidence, theoretically, the quality factor is infinite, the line width disappears, and the quasi-BIC is converted under the remaining oblique incidence angle, and the resonance peak with extremely high Q is appeared. Moreover, with the increase of the incident angle, the Q factor basically does not decrease. This is due to the combination of several BICs, and the quality factor near the BIC satisfies the relationship of being proportional to the negative sixth power of the wave vector, based on this, a new idea can be provided for the design of super surface supporting high quality factor.
[0028] In addition, under the same parameter combination, different incident angles are taken, and the conversion efficiency of the second harmonic is calculated in a super material resonator with super high quality factor and insensitive to the incident angle, and the second harmonic enhancement performance is shown in FIG. Figure 3 、 4 5, it can be seen that the conversion efficiency of the second harmonic above 0.1% can be realized under different incident angles.
[0029] The purpose of the present application is to provide a super material resonator with super high quality factor and insensitive to the incident angle, which solves the problems of easy oxidation of metal, high loss and complex structure in the high quality factor metal super material resonator in the prior art, and the super high Q local resonance not affected by the incident angle can be generated by using a simple dielectric column, and the stable second harmonic enhancement can be realized through the resonance with extremely high quality factor.
[0030] Compared with the metal super material resonator with high quality factor, since the intrinsic loss of metal is inevitable, the super material resonator based on all dielectric can realize higher quality factor, and the structure is simple, does not need multi-layer super material stacking, is insensitive to the incident angle, and has high stability.
[0031] The present application solves the problems of high loss and complex structure in the high quality factor metal super material resonator in the prior art, and through the design of dispersion relation, the working wavelength is shifted extremely small under different incident angles, and the great enhancement of nonlinear response can be realized through the resonance peak with extremely high quality factor.
[0032] The above only describes the preferred embodiments of the present application and is not used to limit the present application, although the present application is described in detail with reference to the foregoing embodiments, the skilled in the art can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to some technical features. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.
Claims
1. A resonator with ultra-high quality factor that is insensitive to the angle of incidence, characterized in that, The resonator is composed of a plurality of units arranged periodically, each of the units having the same structure and being composed of a dielectric column composed of dielectric AlGaAs; The resonator can move the accidental BIC in the momentum space to the center of the Brillouin zone by changing the period constant a, and combine the protected BIC together, so as to excite a resonant peak with super-high quality factor, and the quality factor is proportional to the negative sixth power of the wave vector.
2. The resonator with super-high quality factor which is insensitive to incident angle according to claim 1, characterized in that, The resonator unit has a square cross section.
3. The resonator with super-high quality factor which is insensitive to incident angle according to claim 1, characterized in that, The resonator period is 1080-1100nm, the dielectric column height is 845-855nm, and the dielectric column radius is 265nm.