Dual tuned electromagnetically induced transparent resonator

Abstract

The invention discloses a dual-adjustment electromagnetic induction transparent resonator, belongs to the technical field of wireless communication, and solves the problem that only one transmission spectrum adjustment mode can be realized in the existing active adjustable EIT metamaterial scheme under the irradiation of electromagnetic waves in the same mode. And double adjustment of adjusting the transmission spectrum to a resonance state without an EIT phenomenon and a resonance-free state without the EIT phenomenon cannot be realized. According to the invention, the resonance state of the EIT resonance unit is controlled through the light intensity and / or the temperature, so that the transmission spectrum of the EIT resonance unit is adjusted; when the temperature acting on the EIT resonance unit is independently changed or the temperature and the illumination intensity acting on the EIT resonance unit are simultaneously changed, a transmission spectrum is adjusted to a non-resonance state without the EIT phenomenon from an EIT phenomenon; when the light intensity acting on the EIT resonance unit is independently changed, the transmission spectrum is adjusted from an EIT phenomenon to a resonance state without the EIT phenomenon. The slow-light terahertz switch sensor is mainly applied to the field of slow-light terahertz switch sensors.

Description

Technical Field

[0001] The present invention belongs to the technical field of wireless communication. Background Art

[0002] Due to being able to overcome the limitations of harsh conditions such as extremely low temperature and ultra - strong lasers, the phenomenon of Electromagnetically Induced Transparency (EIT) based on metamaterial technology is regarded as an ideal EIT platform, opening up a new path for the research of EIT phenomenon in the fields of optical storage and terahertz sensors. In order to increase the practicality of EIT metamaterials, the research on actively tunable EIT phenomenon has received great attention. The so - called actively tunable EIT metamaterials generally refer to a class of metamaterials that can adjust the EIT phenomenon by changing external factors, such as incident light intensity, temperature, or voltage, without changing the inherent size of the structure. Existing actively tunable EIT metamaterials have realized the adjustment of parameters such as the coupling strength, frequency, and bandwidth of the EIT phenomenon.

[0003] However, in the existing actively tunable EIT metamaterial solutions, the transmission spectrum of the EIT metamaterial can only be adjusted to one state. Specifically, in most of the existing actively tunable EIT metamaterial solutions, the transmission spectrum of the EIT metamaterial is adjusted to a resonant state without the EIT phenomenon, while in a small number of cases, it can be adjusted to a non - resonant state without the EIT phenomenon. There is no technical solution that can selectively adjust the transmission spectrum of the EIT metamaterial under the irradiation of electromagnetic waves of the same mode to a resonant state without the EIT phenomenon or a non - resonant state without the EIT phenomenon, that is, under the irradiation of electromagnetic waves of the same mode, the transmission spectrum of the EIT metamaterial can be adjusted to a resonant state without the EIT phenomenon or a non - resonant state without the EIT phenomenon, but this active adjustment solution can only selectively adjust the transmission spectrum to one of the resonant state without the EIT phenomenon and the non - resonant state without the EIT phenomenon. This restricts the application of actively tunable EIT metamaterials in fields such as terahertz sensors and terahertz switching devices. The above problems need to be solved urgently. Summary of the Invention

[0004] The purpose of the present invention is to solve the problem that in the existing actively tunable EIT metamaterial solutions under the irradiation of electromagnetic waves of the same mode, only one transmission spectrum adjustment method can be realized, and it is impossible to adjust the transmission spectrum to a resonant state without the EIT phenomenon and a non - resonant state without the EIT phenomenon. The present invention provides a dual - adjustable electromagnetic - induced - transparency resonator.

[0005] The dual - adjustable electromagnetic - induced - transparency resonator includes an array formed by splicing a plurality of EIT resonant units; the resonant state of the EIT resonant units is controlled by light intensity and / or temperature to realize the adjustment of the transmission spectrum of the EIT resonant units.

[0006] When the temperature acting on the EIT resonance unit is changed alone or the temperature and light intensity acting on the EIT resonance unit are changed simultaneously, the transmission spectrum of the EIT resonance unit is adjusted from the state with the EIT phenomenon to the non-resonant state without the EIT phenomenon;

[0007] When the light intensity acting on the EIT resonance unit is changed alone, the transmission spectrum of the EIT resonance unit is adjusted from the state with the EIT phenomenon to the resonant state without the EIT phenomenon;

[0008] Each EIT resonance unit includes an "I"-shaped strip located on a rectangular SiO2 substrate and two oppositely arranged split ring resonators, and the openings of the two split ring resonators face each other, and the "I"-shaped strip is located between the two oppositely arranged split ring resonators;

[0009] The center of the "I"-shaped strip is on the same straight line as the center of the region formed by the two oppositely arranged split ring resonators, and the distance between the two centers is S;

[0010] The "I"-shaped strip is composed of two oppositely arranged aluminum strips and a vanadium dioxide strip sandwiched between the two aluminum strips and perpendicular to the two aluminum strips;

[0011] Each split ring resonator includes two aluminum strips and a hybrid strip, and the two aluminum strips are perpendicular to the horizontally arranged hybrid strip;

[0012] The hybrid strip is made of an aluminum strip and a photosensitive silicon strip sandwiched in the middle of the aluminum strip.

[0013] Preferably, the conductivity of the photosensitive silicon is controlled by the light intensity, and the conductivity of the vanadium dioxide is controlled by the temperature.

[0014] Preferably, the adjustment range of the conductivity of the photosensitive silicon is 10 s / m to 3×10 5 s / m, and the adjustment range of the conductivity of the vanadium dioxide is 200 s / m to 2×10 5 s / m.

[0015] Preferably, the value of S is 5 μm.

[0016] Preferably, in each EIT resonance unit, P x = 100 μm, P y = 120 μm, L1 = 60 μm, L2 = 26 μm, L3 = 2 μm, D = 74 μm, D1 = 19 μm, D2 = 44 μm, w = 5 μm;

[0017] Among them, P x is the length of the rectangular SiO2 substrate, P yW is the width of the rectangular SiO2 substrate, L1 is the length of the hybrid strip in the split-ring resonator, L2 is the length of the aluminum strip in the "I"-shaped strip, L3 is the length of the photosensitive silicon strip in the hybrid strip, D is the vertical height of the region formed by two oppositely arranged split-ring resonators, D1 is the vertical height of the split-ring resonator, D2 is the height of the vanadium dioxide strip in the "I"-shaped strip, and w is the width of the aluminum strip.

[0018] Preferably, the thicknesses of the aluminum strip, the vanadium dioxide strip, and the photosensitive silicon strip are all 5 μm, and the thickness of the rectangular SiO2 substrate is 10 μm.

[0019] Advantages of the present invention:

[0020] The present invention enriches the technical solutions of actively tunable EIT metamaterials and enhances the ability to adjust the EIT phenomenon. The present invention uses vanadium dioxide (VO2) and photosensitive silicon (Si) to design an EIT resonance unit, which is a hybrid EIT structure. The EIT phenomenon generated by this structure is produced by the near-field coupling effect of electric dipole resonance and magnetic dipole resonance. Among them, the electric dipole is the "I"-shaped strip as the bright-mode resonance oscillator unit; the magnetic dipole is the split-ring resonator, serving as the dark-mode resonance oscillator unit.

[0021] The EIT resonance unit of the present invention can, without changing the structural dimensions, adjust the transmission spectrum of the EIT metamaterial to a non-resonant state without the EIT phenomenon by changing the temperature; it can also adjust the transmission spectrum of the EIT metamaterial to a resonant state without the EIT phenomenon by changing the incident light intensity; and when adjusting the temperature and the incident light intensity simultaneously, the transmission spectrum of the EIT metamaterial will be adjusted to a non-resonant state without the EIT phenomenon, overcoming the defect in the prior art that the transmission spectrum of the EIT metamaterial can only adjust the EIT phenomenon to a non-resonant state without the EIT phenomenon or only to a resonant state without the EIT phenomenon. The present invention can achieve dual adjustment to a non-resonant state without the EIT phenomenon and to a resonant state without the EIT phenomenon.

[0022] When the present invention adjusts the temperature and the incident light intensity simultaneously, the transmission spectrum of the EIT metamaterial will be adjusted to a non-resonant state without the EIT phenomenon, which is similar to the change trend of the transmission spectrum of the EIT metamaterial when adjusting the temperature alone, indicating that the adjustment effect of the temperature is more dominant than that of the incident light intensity adjustment. This design can enrich the actively tunable phenomena of EIT metamaterials and provide a new technical solution for slow-light terahertz switching devices. Description of the Drawings

[0023] Figure 1 is a schematic structural diagram of the dual-adjustment electromagnetic-induced transparency resonator described in the present invention;

[0024] Figure 2when the relative conductivity of vanadium dioxide is 2×10 5 S / m, and the conductivity of photosensitive silicon changes from 3×10 5 S / m, the transmission spectrum change diagrams corresponding to the single "I"-shaped strip, the single split-ring resonator, and the EIT resonant unit;

[0025] Figure 3 is the electric field strength distribution diagram; among them, Figure 3 a is the electric field distribution diagram of the single "I"-shaped strip, Figure 3 b is the electric field distribution diagram of the single split-ring resonator, Figure 3 c is the electric field distribution of the EIT resonant unit, Figure 3 d is the magnetic field distribution of the EIT resonant unit, Figure 3 e is the current density distribution diagram of the EIT resonant unit;

[0026] Figure 4 when the relative conductivity of vanadium dioxide is 2×10 5 S / m, and the conductivity of photosensitive silicon changes from 3×10 5 S / m to 100 S / m, the transmission spectrum of the EIT resonant unit;

[0027] Figure 5 when the relative conductivity of vanadium dioxide is 2×10 5 S / m, and the conductivity of photosensitive silicon changes from 3×10 5 S / m to 100 S / m, the group delay curve;

[0028] Figure 6 when the conductivity of photosensitive silicon is maintained at 3×10 5 S / m, and the conductivity of vanadium dioxide changes from 2×10 5 S / m to 200 S / m, the transmission spectrum;

[0029] Figure 7 when the conductivity of photosensitive silicon is maintained at 3×10 5 S / m, and the conductivity of vanadium dioxide changes from 2×10 5 S / m to 200 S / m, the group delay curve diagram;

[0030] Figure 8 is the transmission spectrum when the conductivities of photosensitive silicon and vanadium dioxide are adjusted simultaneously. Specific implementation manner

[0031] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0032] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments may be combined with each other.

[0033] See Figure 1 In this embodiment, the dual - regulated electromagnetically induced transparency resonator includes an array formed by splicing a plurality of EIT resonance units; the resonance state of the EIT resonance unit is controlled by light intensity and / or temperature to achieve the regulation of the transmission spectrum of the EIT resonance unit.

[0034] When the temperature acting on the EIT resonance unit is changed alone or the temperature and light intensity acting on the EIT resonance unit are changed simultaneously, the transmission spectrum of the EIT resonance unit is adjusted from the state with EIT phenomenon to the non - resonance state without EIT phenomenon.

[0035] When the light intensity acting on the EIT resonance unit is changed alone, the transmission spectrum of the EIT resonance unit is adjusted from the state with EIT phenomenon to the resonance state without EIT phenomenon.

[0036] Each EIT resonance unit includes an "I"-shaped strip located on a rectangular SiO2 substrate and two oppositely arranged split - ring resonators, and the openings of the two split - ring resonators face each other, and the "I"-shaped strip is located between the two oppositely arranged split - ring resonators.

[0037] The center of the "I"-shaped strip is on the same straight line as the center of the region formed by the two oppositely arranged split - ring resonators, and the distance between the two centers is S.

[0038] The "I"-shaped strip is composed of two oppositely arranged aluminum strips and a vanadium dioxide strip clamped between the two aluminum strips and perpendicular to the two aluminum strips.

[0039] Each split - ring resonator includes two aluminum strips and a hybrid strip, and the two aluminum strips are perpendicular to the horizontally arranged hybrid strip.

[0040] The hybrid strip is made of an aluminum strip and a photosensitive silicon strip sandwiched in the middle of the aluminum strip.

[0041] Furthermore, the conductivity of the photosensitive silicon is controlled by light intensity, and the conductivity of the vanadium dioxide is controlled by temperature. Among them, the adjustment range of the conductivity of the photosensitive silicon is from 10 s / m to 3×10 5s / m, the conductivity regulation range of vanadium dioxide is from 200 s / m to 2×10 5 s / m.

[0042] When the EIT resonant unit adjusts the conductivity of photosensitive silicon to 3×10 5 s / m and the relative conductivity of vanadium dioxide to 2×10 5 s / m respectively through temperature and light intensity, when an electromagnetic wave perpendicular to the x-y plane with a polarization direction of y is incident on the EIT resonant unit, the "I"-shaped strip composed of aluminum (Al) and vanadium dioxide (VO2) in the present invention can generate an electric dipole resonance, serving as a bright mode resonator in the EIT coupling, while the split ring resonator (SRR) made of aluminum (Al) and photosensitive silicon (Si) does not resonate under the action of the same electromagnetic wave, which is a dark mode resonator. After combining the two together, under the action of the current electromagnetic wave, an EIT phenomenon is generated based on bright-dark coupling, with a transparent peak at 1.27 THz and transmission valleys at 1.19 THz and 1.38 THz, as Figure 2 shown.

[0043] Furthermore, the value of S is 5 μm, the thicknesses of the aluminum strip, vanadium dioxide strip, and photosensitive silicon strip are all 5 μm, and the thickness of the rectangular SiO2 substrate is 10 μm;

[0044] In each EIT resonant unit, P x = 100 μm, P y = 120 μm, L1 = 60 μm, L2 = 26 μm, L3 = 2 μm, D = 74 μm, D1 = 19 μm, D2 = 44 μm, w = 5 μm;

[0045] Among them, P x is the length of the rectangular SiO2 substrate, P y is the width of the rectangular SiO2 substrate, L1 is the length of the hybrid strip in the split ring resonator, L2 is the length of the aluminum strip in the "I"-shaped strip, L3 is the length of the photosensitive silicon strip in the hybrid strip, D is the vertical height of the region formed by two oppositely arranged split ring resonators, D1 is the vertical height of the split ring resonator, D2 is the height of the vanadium dioxide strip in the "I"-shaped strip, and w is the width of the aluminum strip.

[0046] Figure 3 is the electric field intensity distribution diagram; as can be seen from Figure 3 a, under the action of the current electromagnetic wave, the single "I"-shaped strip shows an obvious electric dipole resonance state, being a bright mode resonator, while Figure 3b shows that the single split-ring resonator (i.e., single SRR) is in a non-resonant state and is a dark-mode resonator. After the two are combined, due to the near-field coupling effect of the bright and dark mode resonators, electromagnetic energy is transferred. Figure 3 c to Figure 3 e are respectively the electric field, magnetic field, and current density distribution diagrams of the EIT resonant unit, indicating that the SRR unit in the EIT mechanism is excited and exhibits a magnetic dipole resonance state, verifying that the EIT phenomenon described in the present invention is the near-field coupling mechanism of electric dipole resonance and magnetic dipole resonance.

[0047] Verification test:

[0048] Parameter setting: Set the parameters of the EIT resonant unit as follows: The value of S is 5 μm, the thicknesses of the aluminum strip, vanadium dioxide strip, and photosensitive silicon strip are all 5 μm, and the thickness of the rectangular SiO2 substrate is 10 μm; P x = 100 μm, P y = 120 μm, L1 = 60 μm, L2 = 26 μm, L3 = 2 μm, D = 74 μm, D1 = 19 μm, D2 = 44 μm, w = 5 μm;

[0049] Under the above structural parameters of the EIT resonant unit, verify the technical effects of the dual-tuning electromagnetic induced transparency resonator based on the EIT resonant unit of the present invention, specifically as follows: When the EIT resonant unit adjusts the conductivity of the photosensitive silicon to 3×10 5 S / m and the relative conductivity of vanadium dioxide to 2×10 5 S / m respectively through temperature and light intensity, when the EIT resonant unit is irradiated by an electromagnetic wave perpendicular to the x-y plane with the polarization direction in the y direction, when keeping the relative conductivity of vanadium dioxide at 2×10 5 S / m and reducing the conductivity of the photosensitive silicon, the EIT phenomenon will weaken.

[0050] Figure 4 Shown is the transmission spectrum when the conductivity of the photosensitive silicon decreases from 3×10 5 S / m to 100 S / m. It can be seen from Figure 4 that when the conductivity of the photosensitive silicon drops to 100 S / m, there is no EIT phenomenon in the transmission spectrum, and the transmission spectrum is a resonant curve, which is the resonant curve of the bright-mode resonator.

[0051] Figure 5 For the relative conductivity of vanadium dioxide at 2×10 5 S / m and the conductivity of the photosensitive silicon decreasing from 3×10 5 S / m to 100 S / m, the group delay curve is shown. It can be seen from Figure 5 that the group delay gradually decreases from the maximum of 8.53 ps, indicating that the EIT phenomenon weakens.

[0052] Correspondingly, under the condition of the same incident electromagnetic wave, when the conductivity of the photosensitive silicon is maintained at 3×10 5 s / m and the relative conductivity of vanadium dioxide is decreased, the EIT phenomenon will also be weakened. Figure 6 Shown is the transmission spectrum when the conductivity of vanadium dioxide decreases from 2×10 5 s / m to 200 s / m. It can be seen from Figure 6 the figure that when the conductivity of vanadium dioxide drops to 200 s / m, there is no EIT phenomenon in the transmission spectrum, and the curve is a non-resonant curve (non-resonant state).

[0053] Figure 7 When the conductivity of the photosensitive silicon is maintained at 3×10 5 s / m and the conductivity of vanadium dioxide decreases from 2×10 5 s / m to 200 s / m, the group delay curve is shown. It can be seen from Figure 7 the figure that when the conductivity of vanadium dioxide decreases from 2×10 5 s / m to 200 s / m, the EIT phenomenon is still weakened.

[0054] Observed is the transmission spectrum of the EIT structure when the conductivity of vanadium dioxide is simultaneously adjusted from 2×10 5 s / m to 200 s / m and the conductivity of the photosensitive silicon is adjusted from 3×10 5 s / m to 100 s / m. Figure 8 Shown is the transmission spectrum when the conductivities of vanadium dioxide and photosensitive silicon are simultaneously adjusted. It can be seen from Figure 8 the figure that when the conductivities of the photosensitive silicon and vanadium dioxide are simultaneously decreased, the EIT phenomenon is still weakened, and finally the transmission spectrum is a non-resonant curve, which is consistent with the change trend of the transmission spectrum when the conductivity of the photosensitive silicon is maintained at 3×10 5 s / m and the conductivity of vanadium dioxide is decreased, indicating that when adjusting simultaneously, the adjustment of the bright mode resonant unit (adjusting the conductivity of vanadium dioxide through temperature) has a stronger dominant role.

[0055] Although the present invention has been described herein with reference to particular embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the invention. Therefore, it should be understood that many modifications can be made to the exemplary embodiments, and other arrangements can be designed, as long as they do not depart from the spirit and scope of the invention as defined by the appended claims. It should be understood that the different dependent claims and the features described herein can be combined in a manner different from that described in the original claims. It should also be understood that the features described in connection with a single embodiment can be used in other described embodiments.

Claims

1. Dual-tuning electromagnetically induced transparency resonator, comprising an array formed by splicing a plurality of EIT resonator units; characterized in that, The resonance state of the EIT resonance unit is controlled by light intensity and / or temperature to achieve the adjustment of the transmission spectrum of the EIT resonance unit; When the temperature acting on the EIT resonance unit is changed alone or the temperature and light intensity acting on the EIT resonance unit are changed simultaneously, the transmission spectrum of the EIT resonance unit is adjusted from the state with EIT phenomenon to the non-resonant state without EIT phenomenon; When the light intensity acting on the EIT resonance unit is changed alone, the transmission spectrum of the EIT resonance unit is adjusted from the state with EIT phenomenon to the resonant state without EIT phenomenon; Each EIT resonance unit includes an "I"-shaped strip located on a rectangular SiO2 substrate and two oppositely arranged split-ring resonators, and the openings of the two split-ring resonators face each other, and the "I"-shaped strip is located between the two oppositely arranged split-ring resonators; The center of the "I"-shaped strip is on the same straight line as the center of the region formed by the two oppositely arranged split-ring resonators, and the distance between the two centers is S; The "I"-shaped strip is composed of two oppositely arranged aluminum strips and a vanadium dioxide strip clamped between the two aluminum strips and perpendicular to the two aluminum strips; Each split-ring resonator includes two aluminum strips and a hybrid strip, and the two aluminum strips are perpendicular to the horizontally arranged hybrid strip; The hybrid strip is made of an aluminum strip and a photosensitive silicon strip sandwiched in the middle of the aluminum strip.

2. The dual-tuning electromagnetically induced transparency resonator according to claim 1, characterized in that The conductivity of the photosensitive silicon is controlled by light intensity, and the conductivity of the vanadium dioxide is controlled by temperature.

3. The dual-tuning electromagnetically induced transparency resonator according to claim 1, characterized in that, The conductivity of the photosensitive silicon can be adjusted in the range of 10 S / m to 3×10 5 S / m, and the conductivity of vanadium dioxide can be adjusted in the range of 200 S / m to 2×10 5 S / m.

4. The dual-tuning electromagnetically induced transparency resonator according to claim 1, wherein The value of S is 5μm.

5. The dual-tuning electromagnetic induced transparency resonator according to claim 1, wherein In each EIT resonant unit, P x = 100 μm, P y = 120 μm, L1 = 60 μm, L2 = 26 μm, L3 = 2 μm, D = 74 μm, D1 = 19 μm, D2 = 44 μm, w = 5 μm; Among them, P x is the length of the rectangular SiO2 substrate, P y is the width of the rectangular SiO2 substrate, L1 is the length of the hybrid strip in the split-ring resonator, L2 is the length of the aluminum strip in the "I"-shaped strip, L3 is the length of the photosensitive silicon strip in the hybrid strip, D is the vertical height of the region formed by two oppositely arranged split-ring resonators, D1 is the vertical height of the split-ring resonator, D2 is the height of the vanadium dioxide strip in the "I"-shaped strip, and w is the width of the aluminum strip.

6. The dual-tuning electromagnetically induced transparency resonator according to any one of claims 1 to 5, characterized in that The thicknesses of the aluminum strip, the vanadium dioxide strip, and the photosensitive silicon strip are all 5μm, and the thickness of the rectangular SiO2 substrate is 10μm.

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