CN113866229A - high-Q-value eccentric artificial local surface plasmon quasi-BIC super surface and implementation method thereof - Google Patents

high-Q-value eccentric artificial local surface plasmon quasi-BIC super surface and implementation method thereof Download PDF

Info

Publication number
CN113866229A
CN113866229A CN202111113487.0A CN202111113487A CN113866229A CN 113866229 A CN113866229 A CN 113866229A CN 202111113487 A CN202111113487 A CN 202111113487A CN 113866229 A CN113866229 A CN 113866229A
Authority
CN
China
Prior art keywords
eccentric
bic
quasi
grating
center
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN202111113487.0A
Other languages
Chinese (zh)
Other versions
CN113866229B (en
Inventor
杜朝海
李思琦
韩丰远
高子超
李繁弘
刘濮鲲
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Peking University
Original Assignee
Peking University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Peking University filed Critical Peking University
Priority to CN202111113487.0A priority Critical patent/CN113866229B/en
Publication of CN113866229A publication Critical patent/CN113866229A/en
Application granted granted Critical
Publication of CN113866229B publication Critical patent/CN113866229B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/02Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
    • G01N27/22Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating capacitance
    • G01N27/221Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating capacitance by investigating the dielectric properties

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Investigating Or Analysing Materials By Optical Means (AREA)

Abstract

The invention discloses a high-Q-value eccentric artificial local surface plasmon quasi-BIC super surface and an implementation method thereof. The invention adopts a plurality of eccentric artificial local surface plasmon basic units to be arranged into a periodic two-dimensional array, so that the geometric center and the gravity center of the circular grating have offset, namely the circular grating is an eccentric structure; the eccentric structure breaks the symmetry of the concentric structure, so that a high-order mode is degenerated into a quasi-BIC mode with a high Q value, and the high-order mode is excited; the peak corresponding to the high-order mode is extremely narrow, namely the high-order mode has an extremely high Q value, which is beneficial to improving the sensitivity of electromagnetic wave sensing; the invention has the advantages of multiple resonance points, wide frequency band and field enhancement, and is used for millimeter wave sensing, material detection, tactical stealth, biomedicine and the like.

Description

high-Q-value eccentric artificial local surface plasmon quasi-BIC super surface and implementation method thereof
Technical Field
The invention relates to a millimeter wave sensing technology, in particular to a high-Q-value eccentric artificial local surface plasmon quasi-BIC super surface and an implementation method thereof.
Background
Artificial Localized Surface Plasmons (LSSPs) have received much attention from researchers due to their properties of sub-wavelength manipulation and near-field enhancement. Because the texture structure can reduce the plasma frequency of metal, the microwave frequency band can imitate the natural Local Surface Plasmons (LSPs) of an optical frequency band, and can be made into novel passive microwave devices such as a sensor, a band-pass filter, an Orbital Angular Momentum (OAM) antenna, an electromagnetic stealth coating and the like.
Among them, millimeter wave sensing based on artificial local surface plasmons is a promising application. It has been confirmed by Radar Cross Section (RCS) analysis that various artificial localized surface plasmon modes can be excited when electromagnetic waves are incident from the side. However, when the electromagnetic wave is incident from the front, only the TE of the lowest order can be excited1,1Mode, higher order mode (TE)2,1And above) are Bound States in the symmetrically protected Continuum (BIC) that are not excited. However, in practice, front incidence is the most common case of millimeter wave sensing, such as echo reception of vehicle radar and transmitted wave reception of millimeter wave security inspection, and the phase plane of electromagnetic waves is parallel to the receiving plane.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides a high-Q-value eccentric artificial local surface plasmon Quasi-BIC super surface, and an eccentric structure enables a high-order mode to be degenerated into a Quasi Bound States in the continuous domain (Quasi-BIC) mode with extremely high Q value, so that the Quasi Bound States can be excited by electromagnetic waves incident from the front. Compared with the super-surface of other structures, the structure has the advantages of multiple resonance points, wide frequency band and field enhancement, and can be used for millimeter wave sensing, material detection, tactical stealth, biomedicine and the like.
The invention aims to provide a high-Q-value eccentric artificial local surface plasmon quasi-BIC super surface.
The high-Q-value eccentric artificial local surface plasmon quasi-BIC super surface comprises: base body and eccentric personA work area surface plasmon basic unit; forming M multiplied by N eccentric artificial local surface plasmon basic units distributed in a periodic two-dimensional array on a substrate, wherein M and N are integers more than or equal to 3; each eccentric artificial local surface plasmon basic unit is a circular grating with a hollow circle therein, so that the geometric center and the gravity center of the circular grating are offset, namely the circular grating is in an eccentric structure; the width of the edge of the circular grating is b, and the outer radius of the teeth (teeth) of the circular grating is R2The number of teeth is N, the grating period is d, N is more than 30, so that the grating period d is far less than the wavelength of the incident plane electromagnetic wave, namely the grating period is less than or equal to one tenth of the wavelength of the plane electromagnetic wave, the grating duty ratio is a/d, and the radius of the hollow circle is R1(ii) a There are two eccentric modes to realize the eccentric structure: one is hollow round non-concentric, and the other is uneven grating structure; in the eccentric mode that the hollow circle is not concentric, the teeth of the circular grating are uniformly distributed, and the distance between the center of the hollow circle and the center of the circular grating is delta L; in the eccentric mode of the uneven grating structure, the center of a hollow circle coincides with the center of a circular grating, but teeth of the circular grating are unevenly distributed, namely one or more parameters of grating constant, duty ratio, spacing and length are unevenly distributed, so that the geometric center and the center of gravity of the circular grating are offset, and the spacing between the geometric center and the center of gravity is delta L; the direction of a connecting line between the geometric center and the gravity center of the circular grating is the eccentric displacement direction; the distance between adjacent eccentric artificial local surface plasmon basic units is D, and the period of the periodic two-dimensional array is D +2(b + R)2) (ii) a The normal incidence of a plane electromagnetic wave (TEM) is to the quasi-BIC super surface, namely the wave vector direction of the plane electromagnetic wave is vertical to the quasi-BIC super surface, an equiphase plane is parallel to the quasi-BIC super surface, the electric field and the magnetic field of the plane electromagnetic wave are both parallel to the surface, and the direction of the electric field is parallel to the eccentric displacement direction; in the concentric structure of the circular grating with the geometric center coinciding with the center of gravity, the TE mode of the fundamental mode is used when the planar electromagnetic wave is incident from the front1,1Is a resonant Leaky Mode (Leaky Mode) that can be excited, and a higher order Mode (TE)2,1And above) is a symmetrically protected BIC mode, with no normal component in its far field of radiation, unable to couple with a planar electromagnetic wave, unable to be excited; eccentric knotThe symmetry of a concentric structure is broken, so that a radiation far field of a high-order mode generates a normal component, the high-order mode is degenerated into a symmetrical protection type quasi-BIC mode with a high Q value, and the high-order mode is excited; in quasi-BIC super-surfaces of eccentric structure, the basic mode TE1,1Can still be excited, and the resonant frequency of the resonant circuit has slight change; the number of the high-order modes is multiple, the resonant frequency corresponding to each mode is spaced, and a frequency reference can be provided for the spectrometer; the peak corresponding to the high-order mode is extremely narrow, namely the high-order mode has an extremely high Q value, which is beneficial to improving the sensitivity of electromagnetic wave sensing; the smaller the distance delta L between the center of the hollow circle and the center of the circular grating is, the narrower the peak corresponding to the high-order mode is, and the larger the corresponding Q value is.
The frequency of the planar electromagnetic wave is a microwave frequency band (0.3-300 GHz) or a terahertz frequency band (300-3000 GHz).
The substrate is Printed Circuit Board (PCB) or silicon dioxide (SiO)2) (ii) a For a quasi-BIC super surface applied to a microwave frequency band, a printed circuit board is adopted as a substrate; for the quasi-BIC super surface applied to the terahertz frequency band, the substrate adopts silicon dioxide.
The material of the circular grating is high-conductivity metal, copper or silver.
When the quasi-BIC super surface works in the microwave frequency band, the outer radius R of the teeth of the circular grating2Is millimeter-scale, when the quasi-BIC super surface works in the terahertz frequency band, the outer radius R of the teeth of the circular grating2On the order of microns; r2/4≤R1≤R22; the grating duty ratio a/d is 0.2-0.8; r2/20≤b≤R2/10;R2/4≤D≤2R2
Further, the quasi-BIC super surface is positioned in a background material, the background material is vacuum or gas or liquid with dielectric constant not 1, and trace gas is detected through the change of resonance frequency caused by the change of dielectric constant of a medium of the background material.
The invention also aims to provide a realization method of the high-Q-value eccentric artificial local surface plasmon quasi-BIC super surface.
The invention discloses a method for realizing a high-Q-value eccentric artificial local surface plasmon quasi-BIC super surface, which comprises the following steps of:
1) providing a quasi-BIC super-surface:
a) forming M multiplied by N eccentric artificial local surface plasmon basic units distributed in a periodic two-dimensional array on a substrate, wherein M and N are integers more than or equal to 3;
b) each eccentric artificial local surface plasmon basic unit is a circular grating with a hollow circle therein, so that the geometric center and the gravity center of the circular grating have offset, namely the circular grating is an eccentric structure;
c) the width of the edge of the circular grating is b, and the outer radius of the teeth (teeth) of the circular grating is R2The number of teeth is N, the grating period is d, N is more than 30, so that the grating period d is far less than the wavelength of incident planar electromagnetic waves, namely the grating period is less than or equal to one tenth of the wavelength of the electromagnetic waves, the grating duty ratio is a/d, and the radius of a hollow circle is R1
d) There are two eccentric modes to realize the eccentric structure: one is hollow round non-concentric, and the other is uneven grating structure; the direction of a connecting line between the geometric center and the gravity center of the circular grating is the eccentric displacement direction; the distance between adjacent eccentric artificial local surface plasmon basic units is D, and the period of the periodic two-dimensional array is D +2(b + R)2):
i. In the eccentric mode that the hollow circle is not concentric, the teeth of the circular grating are uniformly distributed, and the distance between the center of the hollow circle and the center of the circular grating is delta L;
ii, in an eccentric mode of uneven grating structure, the center of a hollow circle coincides with the center of a circular grating, but teeth of the circular grating are unevenly distributed, namely one or more parameters of grating constant, duty ratio, spacing and length are unevenly distributed, so that the geometric center and the center of gravity of the circular grating are offset, and the spacing between the geometric center and the center of gravity is delta L;
e) the direction of a connecting line between the geometric center and the gravity center of the circular grating is the eccentric displacement direction; the distance between adjacent eccentric artificial local surface plasmon basic units is D, and the period of the periodic two-dimensional array is D +2(b + R)2);
2) The normal incidence of a plane electromagnetic wave (TEM) is to the quasi-BIC super surface, namely the wave vector direction of the plane electromagnetic wave is vertical to the quasi-BIC super surface, an equiphase plane is parallel to the quasi-BIC super surface, the electric field and the magnetic field of the plane electromagnetic wave are both parallel to the surface, and the direction of the electric field is parallel to the eccentric displacement direction;
3) in the concentric structure of the circular grating with the geometric center coinciding with the center of gravity, the TE mode of the fundamental mode is used when the planar electromagnetic wave is incident from the front1,1Is a resonant Leaky Mode (Leaky Mode) that can be excited, and a higher order Mode (TE)2,1And above) is a symmetrically protected BIC mode, with no normal component in its far field of radiation, unable to couple with a planar electromagnetic wave, unable to be excited; the eccentric structure breaks the symmetry of the concentric structure, so that a radiation far field of a high-order mode generates a normal component, the high-order mode is degenerated into a symmetrical protection type quasi-BIC mode with a high Q value, and the high-order mode is excited;
4) in quasi-BIC super-surfaces of eccentric structure, the basic mode TE1,1Can still be excited, and the resonant frequency of the resonant circuit has slight change; the number of the high-order modes is multiple, the resonant frequency corresponding to each mode is spaced, and a frequency reference can be provided for the spectrometer; the peak corresponding to the high-order mode is extremely narrow, namely the high-order mode has an extremely high Q value, which is beneficial to improving the sensitivity of electromagnetic wave sensing; the smaller the distance delta L between the center of the hollow circle and the center of the circular grating is, the narrower the peak corresponding to the high-order mode is, and the larger the corresponding Q value is.
Further, the quasi-BIC super-surface is placed in a background material, and the trace gas is detected through the change of the resonant frequency caused by the change of the dielectric constant of the medium of the background material.
The invention has the advantages that:
the invention adopts a plurality of eccentric artificial local surface plasmon basic units to be arranged into a periodic two-dimensional array, so that the geometric center and the gravity center of the circular grating have offset, namely the circular grating is an eccentric structure; the eccentric structure breaks the symmetry of the concentric structure, so that a high-order mode is degenerated into a quasi-BIC mode with a high Q value, and the high-order mode is excited; the peak corresponding to the high-order mode is extremely narrow, namely the high-order mode has an extremely high Q value, which is beneficial to improving the sensitivity of electromagnetic wave sensing; the invention has the advantages of multiple resonance points, wide frequency band and field enhancement, and is used for millimeter wave sensing, material detection, tactical stealth, biomedicine and the like.
Drawings
FIG. 1 is a schematic diagram of one embodiment of a high Q eccentric artificial local surface plasmon quasi-BIC super surface of the present invention;
FIG. 2 is a schematic diagram of an eccentric artificial local surface plasmon base unit according to an embodiment of the high Q-value eccentric artificial local surface plasmon quasi-BIC super surface of the present invention;
FIG. 3 is a graph of transmission coefficients of a super-surface of a concentric structure;
FIG. 4 is a graph of the reflection coefficient of a super-surface of a concentric structure;
FIG. 5 shows the upper excited TE of a super-surface with a concentric structure1,1A pattern electric field profile;
FIG. 6 is a graph of transmission coefficients for one embodiment of a high Q eccentric artificial local surface plasmon quasi-BIC super surface of the present invention;
FIG. 7 is a reflection coefficient plot for one embodiment of a high Q eccentric artificial local surface plasmon quasi-BIC super surface of the present invention;
FIG. 8 is TE excited by one embodiment of a high Q eccentric artificial local surface plasmon quasi-BIC super surface of the present invention2,1A pattern electric field profile;
FIG. 9 is TE excited by one embodiment of a high Q eccentric artificial local surface plasmon quasi-BIC super surface of the present invention3,1A pattern electric field profile;
FIG. 10 is a graph of transmission coefficients for one embodiment of a high Q-value eccentric artificial local surface plasmon quasi-BIC super surface of the present invention;
FIG. 11 is a reflection coefficient plot for one embodiment of a high Q-value eccentric artificial local surface plasmon quasi-BIC super surface of the present invention.
Detailed Description
The invention will be further elucidated by means of specific embodiments in the following with reference to the drawing.
As shown in fig. 1, the high-Q-value eccentric artificial local surface plasmon quasi BIC super surface of the present embodiment includes: the device comprises a base body and an eccentric artificial local surface plasmon basic unit; forming M multiplied by N eccentric artificial local surface plasmon basic units distributed in a periodic two-dimensional array on a substrate; as shown in fig. 2, each of the eccentric artificial local surface plasmon basic units is a circular grating having a hollow circle therein, so that the geometric center of the circular grating is offset from the center of gravity, that is, the circular grating has an eccentric structure; the width of the edge of the circular grating is b, and the outer radius of the teeth (teeth) of the circular grating is R2The number of teeth is N, N is more than 30, so that the grating period is far less than the wavelength of the electromagnetic wave, the grating period is d, the grating duty ratio is a/d, and the radius of the hollow circle is R1(ii) a In the embodiment, the deviation of the geometric center is adopted, the teeth of the circular grating are uniformly distributed, and the distance between the center of the hollow circle and the geometric center of the circular grating is delta L; the direction of a connecting line between the geometric center and the gravity center of the circular grating is the eccentric displacement direction; the distance between adjacent eccentric artificial local surface plasmon basic units is D, and the period of the periodic two-dimensional array is D +2(b + R)2)。
In this example, M and N are both 10, R1=5mm,R215mm, 1mm, 0.4 a/D, 60N, 10mm, and 100 eccentric artificial local surface plasmon basic units.
The implementation method of the high-Q-value eccentric artificial local surface plasmon quasi-BIC super surface comprises the following steps:
1) providing a quasi-BIC super-surface:
a) forming 10 multiplied by 10 eccentric artificial local surface plasmon basic units distributed in a periodic two-dimensional array on a substrate;
b) each eccentric artificial local surface plasmon basic unit is a circular grating with a hollow circle therein, so that the geometric center and the gravity center of the circular grating have offset, namely the circular grating is an eccentric structure;
c) the width of the edge of the circular grating is b, and the outer radius of the teeth (teeth) of the circular grating is R2Number of teeth N, grating circumferenceThe period is d, N is more than 30, so that the grating period d is far less than the wavelength of the incident plane electromagnetic wave, namely the grating period is less than or equal to one tenth of the wavelength of the electromagnetic wave, the grating duty ratio is a/d, and the radius of the hollow circle is R1
d) The eccentric mode of hollow circle decentraction realizes eccentric structure:
the teeth of the circular grating are uniformly distributed, and the distance between the center of the hollow circle and the center of the circular grating is delta L;
e) the direction of a connecting line between the geometric center and the gravity center of the circular grating is the eccentric displacement direction; the distance between adjacent eccentric artificial local surface plasmon basic units is D, and the period of the periodic two-dimensional array is D +2(b + R)2);
2) The normal incidence of a plane electromagnetic wave (TEM) is to the quasi-BIC super surface, namely the wave vector direction of the plane electromagnetic wave is vertical to the quasi-BIC super surface, an equiphase plane is parallel to the quasi-BIC super surface, the electric field E and the magnetic field H of the plane electromagnetic wave are both parallel to the surface, and the electric field direction is parallel to the eccentric displacement direction;
3) in the concentric structure of the circular grating with the geometric center coinciding with the center of gravity, the TE mode of the fundamental mode is used when the planar electromagnetic wave is incident from the front1,1Is a resonant Leaky Mode (Leaky Mode) that can be excited, and a higher order Mode (TE)2,1And above) is a symmetrically protected BIC mode, with no normal component in its far field of radiation, unable to couple with a planar electromagnetic wave, unable to be excited; the eccentric structure breaks the symmetry of the concentric structure, so that a radiation far field of a high-order mode generates a normal component, the high-order mode is degenerated into a symmetrical protection type quasi-BIC mode with a high Q value, and the high-order mode is excited;
4) in quasi-BIC super-surfaces of eccentric structure, the basic mode TE1,1Can still be excited, and the resonant frequency of the resonant circuit has slight change; the number of the high-order modes is multiple, the resonant frequency corresponding to each mode is spaced, and a frequency reference can be provided for the spectrometer; the peak corresponding to the high-order mode is extremely narrow, namely the high-order mode has an extremely high Q value, which is beneficial to improving the sensitivity of electromagnetic wave sensing; the smaller the distance delta L between the center of the hollow circle and the center of the circular grating is, the narrower the peak corresponding to the high-order mode is, the pairThe larger the Q value should be.
A concentric structure (Δ d ═ 0mm) super surface is simulated, and symmetric protection is verified so that a high-order mode of an artificial surface plasmon cannot be excited. From the transmission and reflection coefficients (fig. 3 and 4), it can be seen that only one mode is excited on the concentric structure, with the only peak corresponding to TE1,1Mode, the electric field distribution is shown in fig. 5. TE2,1The above higher order modes are not excited due to the symmetric protection. In the concentric structure that the geometric center of the circular grating is coincident with the gravity center, when the circular grating acts with the plane electromagnetic wave, because the high-order mode is protected symmetrically, the circular grating cannot be coupled with the plane electromagnetic wave, the high-order mode cannot be excited, and only TE can be excited1,1Mode, thereby forming a BIC mode.
The eccentric structure breaks the symmetry of the concentric structure, so that a high-order mode is degenerated into a quasi-BIC mode with a high Q value, and the high-order mode is excited; and the peak corresponding to the high-order mode is extremely narrow, namely the high-order mode has an extremely high Q value, which is beneficial to improving the sensitivity of electromagnetic wave sensing. As can be seen from the transmission and reflection coefficients (FIGS. 6 and 7), the concentric structure is shown except for the excitation of TE1,1Mode, can also excite TE2,1The above high-order modes correspond to the three peaks on the right side; reference numerals 1 to 4 in fig. 7 denote 4 patterns, respectively. The peak corresponding to the high-order mode is extremely narrow, which shows that the Q value is extremely high, and the sensitivity of millimeter wave sensing is improved. TE excited on eccentric structure2,1And TE3,1The electric field distribution of the higher-order mode is shown in fig. 8 and 9.
The following exemplifies that this structure can detect a trace gas by a change in resonance frequency caused by a change in dielectric constant of the medium. In the case where the quasi-BIC super-surface background material with Δ L of 2mm is a gas with a dielectric constant of 1.01, the transmission coefficient and the reflection coefficient are simulated again, and as shown in fig. 10 and 11, reference numerals 1 to 4 in fig. 11 represent 4 modes, respectively.
Finally, it is noted that the disclosed embodiments are intended to aid in further understanding of the invention, but those skilled in the art will appreciate that: various substitutions and modifications are possible without departing from the spirit and scope of the invention and the appended claims. Therefore, the invention should not be limited to the embodiments disclosed, but the scope of the invention is defined by the appended claims.

Claims (8)

1. A high Q-value eccentric artificial local surface plasmon quasi-BIC super surface, comprising: the device comprises a base body and an eccentric artificial local surface plasmon basic unit; forming M multiplied by N eccentric artificial local surface plasmon basic units distributed in a periodic two-dimensional array on a substrate, wherein M and N are integers more than or equal to 3; each eccentric artificial local surface plasmon basic unit is a circular grating with a hollow circle therein, so that the geometric center and the gravity center of the circular grating are offset, namely the circular grating is in an eccentric structure; the width of the edge of the circular grating is b, and the outer radius of the teeth of the circular grating is R2The number of teeth is N, the grating period is d, N is more than 30, so that the grating period d is far less than the wavelength of the incident plane electromagnetic wave, namely the grating period is less than or equal to one tenth of the wavelength of the plane electromagnetic wave, the grating duty ratio is a/d, and the radius of the hollow circle is R1(ii) a There are two eccentric modes to realize the eccentric structure: one is hollow round non-concentric, and the other is uneven grating structure; in the eccentric mode that the hollow circle is not concentric, the teeth of the circular grating are uniformly distributed, and the distance between the center of the hollow circle and the center of the circular grating is delta L; in the eccentric mode of the uneven grating structure, the center of a hollow circle coincides with the center of a circular grating, but teeth of the circular grating are unevenly distributed, namely one or more parameters of grating constant, duty ratio, spacing and length are unevenly distributed, so that the geometric center and the center of gravity of the circular grating are offset, and the spacing between the geometric center and the center of gravity is delta L; the direction of a connecting line between the geometric center and the gravity center of the circular grating is the eccentric displacement direction; the distance between adjacent eccentric artificial local surface plasmon basic units is D, and the period of the periodic two-dimensional array is D +2(b + R)2) (ii) a The plane electromagnetic wave is normally incident to the quasi-BIC super surface, namely the wave vector direction of the plane electromagnetic wave is vertical to the quasi-BIC super surface, the equiphase plane is parallel to the quasi-BIC super surface, the electric field and the magnetic field of the plane electromagnetic wave are both parallel to the surface, and the electric field direction isTo a direction parallel to the eccentric displacement direction; in the concentric structure of the circular grating with the geometric center coinciding with the center of gravity, the TE mode of the fundamental mode is used when the planar electromagnetic wave is incident from the front1,1The high-order mode is a symmetrical protected BIC mode, and a radiation far field of the high-order mode has no normal component, cannot be coupled with plane electromagnetic waves and cannot be excited; the eccentric structure breaks the symmetry of the concentric structure, so that a radiation far field of a high-order mode generates a normal component, the high-order mode is degenerated into a symmetrical protection type quasi-BIC mode with a high Q value, and the high-order mode is excited; in quasi-BIC super-surfaces of eccentric structure, the basic mode TE1,1Can still be excited, and the resonant frequency of the resonant circuit has slight change; the number of the high-order modes is multiple, the resonant frequency corresponding to each mode is spaced, and a frequency reference can be provided for the spectrometer; the peak corresponding to the high-order mode is extremely narrow, namely the high-order mode has an extremely high Q value, which is beneficial to improving the sensitivity of electromagnetic wave sensing; the smaller the distance delta L between the center of the hollow circle and the center of the circular grating is, the narrower the peak corresponding to the high-order mode is, and the larger the corresponding Q value is.
2. The quasi-BIC super-surface of claim 1, wherein for a quasi-BIC super-surface applied to a microwave frequency band, the substrate employs a printed circuit board; for the quasi-BIC super surface applied to the terahertz frequency band, the substrate is made of silicon dioxide.
3. A quasi-BIC super-surface as claimed in claim 1, wherein the circular grating is made of a high conductivity metal.
4. The quasi-BIC super-surface of claim 1, wherein the teeth of the circular grating have an outer radius R when the quasi-BIC super-surface operates in a microwave frequency band2In the millimeter order; when the quasi-BIC super surface works in the terahertz frequency band, the outer radius R of the teeth of the circular grating2On the order of microns.
5. A quasi-BIC super surface according to claim 1,width b of edge of circular grating, outer radius R of tooth of circular grating2Grating duty cycle a/d and radius of the hollow circle and R1Satisfies the relationship: r2/4≤R1≤R22; the grating duty ratio a/d is 0.2-0.8; r2/20≤b≤R2/10。
6. The quasi-BIC super-surface of claim 1, wherein a distance D between adjacent eccentric artificial local surface plasmon base units satisfies: r2/4≤D≤2R2
7. The method for realizing the high-Q eccentric artificial local area surface plasmon quasi-BIC super surface according to claim 1, wherein the method comprises the following steps:
1) providing a quasi-BIC super-surface:
a) forming M multiplied by N eccentric artificial local surface plasmon basic units distributed in a periodic two-dimensional array on a substrate, wherein M and N are integers more than or equal to 3;
b) each eccentric artificial local surface plasmon basic unit is a circular grating with a hollow circle therein, so that the geometric center and the gravity center of the circular grating have offset, namely the circular grating is an eccentric structure;
c) the width of the edge of the circular grating is b, and the outer radius of the teeth of the circular grating is R2The number of teeth is N, the grating period is d, N is more than 30, so that the grating period d is far less than the wavelength of incident planar electromagnetic waves, namely the grating period is less than or equal to one tenth of the wavelength of the electromagnetic waves, the grating duty ratio is a/d, and the radius of a hollow circle is R1
d) There are two eccentric modes to realize the eccentric structure: one is hollow round non-concentric, and the other is uneven grating structure; the direction of a connecting line between the geometric center and the gravity center of the circular grating is the eccentric displacement direction; the distance between adjacent eccentric artificial local surface plasmon basic units is D, and the period of the periodic two-dimensional array is D +2(b + R)2):
i. In the eccentric mode that the hollow circle is not concentric, the teeth of the circular grating are uniformly distributed, and the distance between the center of the hollow circle and the center of the circular grating is delta L;
ii, in an eccentric mode of uneven grating structure, the center of a hollow circle coincides with the center of a circular grating, but teeth of the circular grating are unevenly distributed, namely one or more parameters of grating constant, duty ratio, spacing and length are unevenly distributed, so that the geometric center and the center of gravity of the circular grating are offset, and the spacing between the geometric center and the center of gravity is delta L;
e) the direction of a connecting line between the geometric center and the gravity center of the circular grating is the eccentric displacement direction; the distance between adjacent eccentric artificial local surface plasmon basic units is D, and the period of the periodic two-dimensional array is D +2(b + R)2);
2) The plane electromagnetic wave is normally incident to the quasi-BIC super surface, namely the wave vector direction of the plane electromagnetic wave is vertical to the quasi-BIC super surface, the equiphase plane is parallel to the quasi-BIC super surface, the electric field and the magnetic field of the plane electromagnetic wave are both parallel to the surface, and the electric field direction is parallel to the eccentric displacement direction;
3) in the concentric structure of the circular grating with the geometric center coinciding with the center of gravity, the TE mode of the fundamental mode is used when the planar electromagnetic wave is incident from the front1,1Is a resonant leaky mode that can be excited, and a higher order mode (TE)2,1And above) is a symmetrically protected BIC mode, with no normal component in its far field of radiation, unable to couple with a planar electromagnetic wave, unable to be excited; the eccentric structure breaks the symmetry of the concentric structure, so that a radiation far field of a high-order mode generates a normal component, the high-order mode is degenerated into a symmetrical protection type quasi-BIC mode with a high Q value, and the high-order mode is excited;
4) in quasi-BIC super-surfaces of eccentric structure, the basic mode TE1,1Can still be excited, and the resonant frequency of the resonant circuit has slight change; the number of the high-order modes is multiple, the resonant frequency corresponding to each mode is spaced, and a frequency reference can be provided for the spectrometer; the peak corresponding to the high-order mode is extremely narrow, namely the high-order mode has an extremely high Q value, which is beneficial to improving the sensitivity of electromagnetic wave sensing; the smaller the distance delta L between the center of the hollow circle and the center of the circular grating is, the narrower the peak corresponding to the high-order mode is, and the larger the corresponding Q value is.
8. The method of claim 7, wherein the quasi-BIC super-surface is placed in a background material, and the trace gas is detected by a change in resonant frequency caused by a change in dielectric constant of a medium of the background material.
CN202111113487.0A 2021-09-23 2021-09-23 high-Q-value eccentric artificial local surface plasmon quasi-BIC super surface and implementation method thereof Active CN113866229B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202111113487.0A CN113866229B (en) 2021-09-23 2021-09-23 high-Q-value eccentric artificial local surface plasmon quasi-BIC super surface and implementation method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202111113487.0A CN113866229B (en) 2021-09-23 2021-09-23 high-Q-value eccentric artificial local surface plasmon quasi-BIC super surface and implementation method thereof

Publications (2)

Publication Number Publication Date
CN113866229A true CN113866229A (en) 2021-12-31
CN113866229B CN113866229B (en) 2022-07-26

Family

ID=78993488

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202111113487.0A Active CN113866229B (en) 2021-09-23 2021-09-23 high-Q-value eccentric artificial local surface plasmon quasi-BIC super surface and implementation method thereof

Country Status (1)

Country Link
CN (1) CN113866229B (en)

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1965226A (en) * 2004-06-11 2007-05-16 国立大学法人岐阜大学 Optical waveguide
US20140363127A1 (en) * 2011-09-13 2014-12-11 Universiteit Gent Integrated Photonics Waveguide Grating Coupler
CN105911621A (en) * 2016-05-26 2016-08-31 北京大学 Coupled photon-plasmon micro cavity with focused energy, preparation method and applications thereof
CN206163672U (en) * 2016-11-25 2017-05-10 厦门大学 Artificial surface etc. are from excimer waveguide based on spiral minor matters structure
CN106951814A (en) * 2016-01-06 2017-07-14 哈尔滨理工大学 The eccentric computational methods of Circular gratings of encoder bias adjustment system
WO2017178746A1 (en) * 2016-04-11 2017-10-19 Horiba France Sas A probe for an apparatus for measuring interaction between a sample, a tip of a near-field device and an exciting electromagnetic beam and a measuring apparatus comprising such a probe
CN107275791A (en) * 2017-06-15 2017-10-20 中国人民解放军空军工程大学 Artificial surface phasmon coupler based on the super surface of transmission-type phase gradient
CN109974628A (en) * 2019-04-09 2019-07-05 合肥工业大学 A kind of circular raster sensor angle error modification method based on Analysis of error source
CN111697307A (en) * 2020-05-28 2020-09-22 北京大学 Artificial local surface plasmon resonator applied to gyrotron and method

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1965226A (en) * 2004-06-11 2007-05-16 国立大学法人岐阜大学 Optical waveguide
US20140363127A1 (en) * 2011-09-13 2014-12-11 Universiteit Gent Integrated Photonics Waveguide Grating Coupler
CN106951814A (en) * 2016-01-06 2017-07-14 哈尔滨理工大学 The eccentric computational methods of Circular gratings of encoder bias adjustment system
WO2017178746A1 (en) * 2016-04-11 2017-10-19 Horiba France Sas A probe for an apparatus for measuring interaction between a sample, a tip of a near-field device and an exciting electromagnetic beam and a measuring apparatus comprising such a probe
CN105911621A (en) * 2016-05-26 2016-08-31 北京大学 Coupled photon-plasmon micro cavity with focused energy, preparation method and applications thereof
CN206163672U (en) * 2016-11-25 2017-05-10 厦门大学 Artificial surface etc. are from excimer waveguide based on spiral minor matters structure
CN107275791A (en) * 2017-06-15 2017-10-20 中国人民解放军空军工程大学 Artificial surface phasmon coupler based on the super surface of transmission-type phase gradient
CN109974628A (en) * 2019-04-09 2019-07-05 合肥工业大学 A kind of circular raster sensor angle error modification method based on Analysis of error source
CN111697307A (en) * 2020-05-28 2020-09-22 北京大学 Artificial local surface plasmon resonator applied to gyrotron and method

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
王兆华等: "不对称纳米环/椭球二聚体的高阶表面等离激元共振特性", 《科学技术与工程》 *

Also Published As

Publication number Publication date
CN113866229B (en) 2022-07-26

Similar Documents

Publication Publication Date Title
Yin et al. Frequency-controlled broad-angle beam scanning of patch array fed by spoof surface plasmon polaritons
Hong et al. Highly selective frequency selective surface with ultrawideband rejection
US20040227668A1 (en) Steerable leaky wave antenna capable of both forward and backward radiation
WO2009107684A1 (en) Artificial medium
JP2000124702A (en) Electromagnetic signal filter, filtering method and delay circuit
JP2002510886A (en) Circuit and method for removing metal surface current
CN109004341A (en) Substrate integration wave-guide Sine Modulated leaky-wave antenna
WO2007114554A1 (en) High impedance surface structure using artificial magnetic conductor, and antenna and electromagnetic device using the same structure
EP1854173A1 (en) Method and arrangement for reducing the radar cross section of integrated antennas
CN107181066A (en) A kind of double wideband polarization converters based on the super surface of anisotropy
Naqui et al. Microwave sensors based on symmetry properties of resonator-loaded transmission lines
CN105789905B (en) A kind of super surface of gyromagnet substrate based on metallic film antistructure
CN109742554B (en) Double-frequency Ku waveband circularly polarized sensitive wave absorber
Zhou et al. Reflectivity of planar metallic fractal patterns
Han et al. A frequency-scanning antenna based on hybridization of the quasi-TEM mode and spoof surface plasmon polaritons mode
Tong et al. Anisotropic index-near-zero metamaterials for enhanced directional acoustic emission
CN108832304B (en) Ultrahigh frequency two-phase modulation board with dual-polarized frequency selection surface and use method thereof
CN109059971B (en) Sensor with three-hole seam structure
CN113866229B (en) high-Q-value eccentric artificial local surface plasmon quasi-BIC super surface and implementation method thereof
WO2011128036A1 (en) Absorber for electromagnetic radiation
CN107885404B (en) Position detection method based on surface electromagnetic wave and position sensor
CN107732378A (en) Frequency multiplication spatial filter
CN107994303A (en) The spatial filter of low section
CN113394570A (en) Low-profile low-incidence-angle-sensitivity wave-absorbing surface and manufacturing process thereof
CN207781850U (en) Frequency multiplication spatial filter

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant