This is a U.S. National Phase Application under 35 U.S.C. § 371 of International Patent Application No. PCT/CN2011/081367, filed Oct. 27, 2011, and claims the priority of Chinese Patent Application Nos. 201110131817.9, filed May 20, 2011, 201110120003.5, May 10, 2011, 201110070889.7, Mar. 23, 2011 and 201110061804.9, filed Mar. 15, 2011 all of which are incorporated by reference herein.
The exemplary disclosure relates to electromagnetic field, and particularly, to an artificial microstructure and an artificial electromagnetic material using the same.
Metamaterial is a new academic vocabulary of 21st century in physics in recent years, and is usually mentioned in scientific literatures. Three important characteristics of the metamaterial include: (1) Metamaterial is usually a composite with novel artificial structure; (2) Metamaterial has extraordinary physical properties (which generally do not exist in materials of the nature); (3) Property of the metamaterial is not generally determined by the intrinsic nature of the constituent material, but is mainly determined by the artificial structure.
Overall, metamaterial is a material based on artificial structure serving as basic unit, and based on spatial arrangement of the basic units in special way. And metamaterial is a new material having special electromagnetic effect. Property of the electromagnetic effect is characterized by its artificial structure. By orderly designing key physical scale of the material structure, limitations of some of the apparent laws of the nature can be overcame, thus obtaining extraordinary material nature beyond ordinary property inherent in the nature.
Metamaterial includes artificial structure, wherein the electromagnetic response of the artificial structure mainly depends on the topological feature and size of structural units.
Metamaterial further includes matrix material with artificial structures attached thereon. The matrix material is used to support the artificial structure, and can be any material different from the artificial structure.
The artificial structure and the matrix material overlap with each other spatially to generate an equivalent dielectric constant ξ and a magnetic permeability μ. The two physical parameters correspond to an electric field response of the material and magnetic response, respectively. Therefore, designing the artificial structure of the metamaterial is the most important part in the field of metamaterial. How to attain a metamaterial, and to further improve the electromagnetic properties of the existing magnetic material, thus replacing the existing magnetic material in actual applications have become a major problem in the development of modern technology.
Therefore, there is room for improvement within the art.
In accordance with one aspect of the disclosure, an artificial microstructure is disclosed. The artificial microstructure used in artificial electromagnetic material includes a first line segment and a second line segment. The second line segment is perpendicular to the first line segment. The first line segment and the second line segment intersect with each other to form a cross-type structure.
In one embodiment of the disclosure, the artificial microstructure includes a number of third segments, and distal ends of the first line segment and the second line segment are respectively connected to the third line segments.
In one embodiment of the disclosure, a distal end of the third line segment extends outward in a direction 45 degrees relative to the first line segment or the second line segment.
In one embodiment of the disclosure, the artificial microstructure includes a line segment group, the line segment group includes a number of fourth line segments, each of the third segments has a fourth line segment vertically connected to both ends thereof.
In one embodiment of the disclosure, the artificial microstructure comprises N line segment groups, each line segment of the N segment group is connected to a distal end of the line segment of the N−1 line segment group, and is perpendicular to the line segment of the N−1 segment group, wherein N represents an integer greater than 1.
In one embodiment of the disclosure, a distal end of the first line segment and a distal end of the second line segment each include a curve portion.
In one embodiment of the disclosure, the curve portion includes at least one circuitous curve.
In one embodiment of the disclosure, the circuitous curve of the curve portion is round angle, right angle, or acute angle.
In one embodiment of the disclosure, the artificial microstructure includes a plurality of third line segments, and the curve portion is connected to a corresponding third line segment.
In one embodiment of the disclosure, the first line segment and the second line segment intersect with each other to form four parts, each of the parts and a corresponding curve portion thereof form a spiral.
In one embodiment of the disclosure, two curve portions located at a same imaginary line of the first line segment or the second line segment are symmetric relative to each other.
In one embodiment of the disclosure, the spiral is rectangular spiral or triangular spiral.
In one embodiment of the disclosure, the first line segments and the second line segments of a number of artificial microstructures intersect with each other at an imaginary central point.
In one embodiment of the disclosure, each curve portion coincides with a neighboring curve portion if such curve portion rotates 360/M degrees about an imaginary point intersected by the first line segment and the segment and served as a rotation center, wherein M represents the number of curve portion.
In one embodiment of the disclosure, the artificial microstructure includes a sixth line segment, the sixth line segment is perpendicular to the first line segment and the second line segment, and the sixth line segment, the first line segment and the second line segment interest at a point.
In one embodiment of the disclosure, the artificial microstructure includes a number third line segments, a distal end of the first line segment and a distal end of the second line segment each are respectively connected to the third line segments.
In one embodiment of the disclosure, the artificial microstructure includes a line segment group, the line segment group includes a number of fourth line segments, each of the third segments has a fourth line segment vertically connected to both ends thereof.
In one embodiment of the disclosure, the artificial microstructure includes N line segment groups, each line segment of the N segment group is connected to a distal end of the line segment of the N−1 line segment group, and is perpendicular to the line segment of the N−1 segment group, wherein N represents an integer greater than 1.
In one embodiment of the disclosure, lengths of each line segment of the N segment group are equal to each other or different to each other.
In one embodiment of the disclosure, the artificial microstructures are mirror images of each other along an imaginary center axis.
In one embodiment of the disclosure, size of the artificial microstructure is equal to or less than one fifth of the wavelength of a corresponding electromagnetic wave, which the artificial microstructure generates a response to.
In accordance with another aspect of the disclosure, an artificial electromagnetic material is disclosed. The artificial electromagnetic material includes a substrate. The substrate includes a number of structural units. The artificial microstructure above is arranged in the corresponding structural unit.
Using the present disclosure, the metamaterial can reduce a volume of the artificial microstructure, and leads to a miniaturization of an electronic component or an electronic device. The artificial microstructure of the present disclosure can obviously increase the absolute value of a minus permeability of the metamaterial and satisfy some specific conditions to obtain the minus permeability.
In one embodiment of the disclosure, a size of the structural unit equal to or less than one tenth of the wavelength of the response electromagnetic.
In one embodiment of the disclosure, the substrate insulating material.
In one embodiment of the disclosure, dielectric constant and magnetic permeability of the artificial electromagnetic material is less than zero.
Artificial electromagnetic materials of the above embodiments are a new material with special electromagnetic effects. The artificial electromagnetic materials can replace the existing magnetic material, and can be applied to a variety of applications. For example, the artificial electromagnetic materials can be applied to electromagnetic wave propagation modulation materials and devices, such as smart antenna, angle zoom, or the modulation of the waveguide system applied to the electromagnetic mode, functional polarization modulation devices, microwave circuit, THz (terahertz), and optical application.
Other advantages and novel features of the present disclosure will become more apparent from the following detailed description of preferred embodiment when taken in conjunction with the accompanying drawings.
The accompanying drawings facilitate an understanding of the various embodiments of this invention. In such drawings:
To improve the electromagnetic characteristics of typical electromagnetic materials in the existing technology, the present disclosure provides an artificial electromagnetic material. The artificial electromagnetic material can be used to replace the existing electromagnetic material, and used in varied electromagnetic application system.
Referring to
Using the artificial microstructures as shown in
The structural units 603 of the artificial electromagnetic material 600 are arrayed in row (x axis direction) and column (y axis direction perpendicular to the x axis direction). The structural units 603 each include an artificial microstructure 602.
The first line segment 602a and the second line segment 602b of the artificial microstructure 602 intersect at point O. The first line segment 602a and the second line segment 602b can be divided into four branches A, B, C and D. One end of each branch A, B, C or D is connected to the point O, and the other end is a free end. Each free end includes a curve portion 602c. Each curve portion 602c includes at least one circuitous curve. In this embodiment, the curve portion of the circuitous curve is a right angle. Any branch A, B, C or D coincides with another corresponding branch if it rotates 90, 180, and 270 degrees about point O.
As shown in
As shown in
As shown in
As shown in
As shown in
In the embodiments as shown in
Referring from
The spiral in this embodiment is a triangular spiral. In this embodiment, the triangular spiral is consisted of a number of lines connected with each other in sequence. The lines are divided into three groups. The lines in each group are parallel to each other. Three lines can be selected randomly from three groups respectively. The three lines extend and intersect with each other to form a triangular. Such spiral is a triangular spiral. In addition, the spiral in this embodiment is an isosceles triangle spiral, that is, the above mentioned three lines extend and intersect with each other to form an isosceles triangular.
Referring from
The spiral in this embodiment is a rectangular spiral. In this embodiment, the rectangular spiral is consisted of a number of lines connected with each other in sequence. The lines are divided into four groups. The lines in each group are parallel to each other. The four lines can be selected randomly from four groups respectively. The four lines each extend and intersect with a neighboring line to form a rectangular. Such spiral is a rectangular spiral.
Referring from
Each of the first spiral 152c and the second spiral 152d is an isosceles right triangle spiral. An area of the first spiral 152c or the second spiral 152d is one eighth of an area of the structural unit 153.
Referring also to
The spiral 162c, 162d each are isosceles right triangle spiral, and snaked extend outward from an corresponding inner endpoints P10, P11 to the outer endpoints P20 and P21. An area of each spiral is one eighth of an area of the structural unit 163.
For any substrate unit with particular size, such substrate unit can snaked extends as much as possible on an surface area thereof. Comparing to the artificial microstructure made of traditional artificial electromagnetic material, the artificial microstructure in the present disclosure is much longer.
In existing technologies, each artificial microstructure can be equal to inductance, capacitance and resistance. By changing a length of the lines, an equivalent inductance can be changed accordingly. The opposite area of the bipolar plate of the capacitor is equal to the length between two adjacent lines relative to other multiplied by thickness of the lines. Therefore, for a specific structural unit, if other conditions are same, the equivalent inductance and the capacitance increase along with length of the artificial microstructure. Accordingly, dielectric constant of the material unit increases along with length of the artificial microstructure. In addition, the formula n=√{square root over (∈μ)} indicates that the refractive index n increases along with length of the artificial microstructure.
Preferably, the spiral of the artificial microstructure as shown in
Referring to
Referring to
Referring to
Sizes of the above mentioned artificial microstructures 182 can be same to each other, and uniformly arranged on the substrate. In alternative embodiments, the sizes of the artificial microstructures 182 can be different from each other, and uniformly arranged on the substrate. In other alternative embodiments, the sizes of the artificial microstructures 182 can be same to each other, but unevenly arranged on the substrate. For example, density of the artificial microstructures 182 in one place can be greater while density of the artificial microstructures 182 in another place is less. In further other alternative embodiments, the sizes of the artificial microstructures 182 can be different from each other, and unevenly arranged on the substrate.
Referring to
In other embodiments, a number of third line segment group perpendicular to the fifth line segments 192e can be set at distal ends of the fifth line segments 192e, and a number of fourth line segment group perpendicular to the third line segments can be set at distal ends of the third line segments. Similarly, more topology structure can be derived therefrom, such structure is similar to the snowflake structure, and is derivative structure of the snowflake structure.
In the derivative structure based on the snowflake structure, length a of the first line segment 182a, length b of the second line segment 182b, and length c of the third line segment 182a are independent variables, and can be any length value. The single snowflake artificial structure show different property when different length value is selected. The lengths d1, d2, e1, e2, f1 and f2 corresponding to the fifth line segments D1, D2, E1, E2, F1, F2 can be any length value. In addition, the fifth line segments D1 and D2, E1 and E2, F1 and F2 can be spatially parallel to each other, or not spatially parallel to each other. Different property of the single snowflake artificial structure is determined by the lengths and location relationships of the fifth line segments.
Only when a, b and c are equal to each other, d1, d2, e1, e2, f1 and f2 accordingly are equal to each other, and the fifth line segments located on a same straight line are parallel to each other. The fifth line segments accordingly parallel to the sixth line segment. When the fifth line segment F1, F2 are parallel to the first line segment 182a, respectively, the single snowflake structure has a symmetric structure, and the structural unit with the snowflake structure therein shows isotropic property toward the electromagnetic wave. When the artificial microstructure includes N line segment groups, all the line segments in the Nth line segment group is parallel to each other, and have a same length. In addition, all the line segments in the Nth line segment group is parallel to any of the first line segment 182a, the second line segment 182b, and the sixth line segment 182f, if the derivative structure is needed to show isotropic property, otherwise the derivative structure show anisotropy property. In the present disclosure, isotropic property and anisotropy property can be achieved when necessary.
Artificial electromagnetic materials as shown in
By designing the structural arrangement of the artificial microstructure, and presetting electromagnetic properties of the artificial electromagnetic material in each three-dimensional coordinates of the space, the electromagnetic properties can be uniform rather than gradient. The electromagnetic properties can be otherwise uneven and gradient according to actual needs. In the present disclosure.
Dimension and arrangement structure of the artificial microstructure can be changed by designing, optimizing, and processing the artificial electromagnetic material, such that the dielectric constant ξ and the magnetic permeability μ of the artificial electromagnetic material can be changed according b any preset value. In addition, propagation direction of the magnetic field also can be changed. In the present disclosure, the gradient, non-gradient property is referred to the gradient, non-gradient property of the dielectric constant ξ and the magnetic permeability μ. Propagation direction of the magnetic field and the dielectric constant ξ, as well as the magnetic permeability μ can be controlled by controlling the structure of the artificial electromagnetic material.
In addition to the above mentioned property, resonant frequency of artificial electromagnetic material can be tuned by changing the single snowflake artificial structure, the microstructure and implementation. That is, tuning of the resonant frequency of artificial electromagnetic material can be achieved by changing the material, a single microstructure, or material of the substrate.
Referring to
Referring to
When the electromagnetic wave incident from a direction perpendicular to the microstructure, the microstructure does not response to the magnetic fields. When the microstructure is spatial symmetric and has isotropic response, the microstructure have the same response toward the incident electromagnetic waves in all directions. That is, the microstructure has a same response value along the X, Y and Z axes. As mentioned above, when the microstructure form an artificial electromagnetic material, if the artificial electromagnetic materials has isotropic properties, response value of the artificial electromagnetic materials in the X, Y and Z axes component are uniform. On the contrary, if it is anisotropy, the response value is uneven distribution, resulting in convergence of electromagnetic waves, offset, etc. When the electromagnetic wave incident vertical to the artificial electromagnetic materials, and through the artificial electromagnetic materials, propagation direction of the electromagnetic wave is deflected according to the preset dielectric constant and magnetic permeability. Generally, the deflection is generated toward a direction of which the absolute value of the dielectric constant and magnetic permeability is great, thus achieving aggregation and offset of the electromagnetic wave. When the electromagnetic wave incident straightly into the artificial electromagnetic materials, and is emitted from the other direction parallel to the incident direction, the incident light and the emitted light are parallel to translation of the communication line horizontally shifted.
Artificial electromagnetic materials of the above embodiments are new material with special electromagnetic effects. The artificial electromagnetic materials can replace the existing magnetic material, and can be applied to a variety of applications. For example, the artificial electromagnetic materials can be applied to electromagnetic wave propagation modulation materials and devices, such as smart antenna, angle zoom, or the modulation of the waveguide system applied to the electromagnetic mode, functional polarization modulation devices, microwave circuit, THz (terahertz), and optical application.
Although the present disclosure has been specifically described on the basis of the exemplary embodiment thereof, the disclosure is not to be construed as being limited thereto. Various changes or modifications may be made to the embodiment without departing from the scope and spirit of the disclosure.
Number | Date | Country | Kind |
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2011 1 0061804 | Mar 2011 | CN | national |
2011 1 0070889 | Mar 2011 | CN | national |
2011 1 0120003 | May 2011 | CN | national |
2011 1 0131817 | May 2011 | CN | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/CN2011/081367 | 10/27/2011 | WO | 00 | 8/7/2012 |
Publishing Document | Publishing Date | Country | Kind |
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WO2012/122803 | 9/20/2012 | WO | A |
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Number | Date | Country | |
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20140011002 A1 | Jan 2014 | US |