KR101593790B1 - Apparatus and method for splitting light and surface plasmon polariton from incident light - Google Patents

Abstract

The optical plasmon separator according to embodiments of the present invention may include a first dielectric optical waveguide, a second dielectric optical waveguide, and a plasmonic waveguide. The first dielectric optical waveguide may be formed in the dielectric clad so as to extend from the input optical waveguide to the output optical waveguide. The second dielectric optical waveguide may be formed in the dielectric clad and branched from the input optical waveguide and shorter than the first dielectric optical waveguide. The plasmonic waveguide may be composed of at least one metal layer formed in the dielectric clad so as to be in contact with the end of the second dielectric optical waveguide.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and a method for separating light and a surface plasmon polariton from an incident light,

The present invention relates to a surface plasmon polariton, and more particularly, to a light plasmon separation technique.

Plasmon refers to pseudo-particles for treating such vibrations as if they were a single particle when free electrons in the metal collectively oscillate under certain conditions. When plasmons are localized to the surface of the metal, they are called surface plasmons.

Surface plasmon resonance is called surface plasmon resonance when light from the visible to near-infrared band enters the metal surface and the surface plasmon interacts with the surface plasmon at a specific wavelength. This phenomenon is characterized by the golden color of gold Or a smooth metal surface is a fundamental principle that shows a distinctive metallic luster.

In particular, when a surface plasmon is generated in a metal thin film through strong interaction with a photon incident in a TM mode at the interface between the metal thin film and the dielectric, a near field propagating along with the surface plasmon appears along the interface. Surface waves are treated as one similar particle and are called surface plasmon polaritons (SPP).

On the other hand, in general, optically diverse visible-infrared band light generally has advantages of high operating speed, wide bandwidth, non-coherence, low loss, etc. However, in order to positively utilize it in the information technology field, Problems and problems of light control should be solved. The problem of integration is due to the fundamental restriction that the light wave can not be focused in a range smaller than the wavelength. It is called the diffraction limit of light. Therefore, the limit of line width in integrated optics is about 0.5 ~ 1μm, Is very large compared to ~ 100 nm.

On the other hand, the surface plasmon polariton (SPP) is able to overcome the optical diffraction limit because the energy of the light wave is strongly focused within a range narrower than the wavelength of the light wave incident from the metal thin film and the dielectric interface. Plasmonics is the technology and field that implement devices that constrain, propagate, transmit, receive, distribute, combine, reflect, and filter SPP waves using these characteristics.

However, plasmonics has a strong linearity due to the unique longitudinal wave characteristics of SPP, and thus it is difficult to implement SPP mode generation, transmission / reception, transmission, replication, amplification and switching.

Accordingly, it is difficult to realize pure plasmonics in the near future, and it is expected that plasmonics will coexist with optical communication or optical communication technology spreading earlier. Accordingly, there is a need for elements capable of handling light and SPP together.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an optical plasmon separation apparatus and method.

An object of the present invention is to provide an optical plasmon separation apparatus and method capable of separating an incident optical signal into a surface plasmon polariton (SPP) having optical signal information and an optical signal.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an optical plasmon separation apparatus and method having a relatively small dimension.

The solution to the problem of the present invention is not limited to those mentioned above, and other solutions not mentioned can be clearly understood by those skilled in the art from the following description.

According to an aspect of the present invention, there is provided a photoplasmon separation apparatus comprising:

A first dielectric optical waveguide formed in the dielectric clad so as to extend from the input optical waveguide to the output optical waveguide;

A second dielectric optical waveguide branched from the input optical waveguide and shorter than the first dielectric optical waveguide, in the dielectric clad; And

And a plasmon waveguide formed of at least one metal layer formed in the dielectric clad so as to be in contact with an end of the second dielectric optical waveguide.

According to one embodiment, at least one metal layer of the plasmonic waveguide

And at least two metal layers formed discontinuously with a gap in the dielectric clad.

According to one embodiment, the extending directions of some metal layers of the at least two metal layers may not be parallel to each other.

According to one embodiment, the extending directions of some of the at least two metal layers and some of the metal layers may be at an acute angle with respect to each other.

According to one embodiment, the plasmonic waveguide comprises first to Nth metal layers,

Wherein the first to Nth metal layers are on the same plane,

The direction in which light is incident on the first metal layer from the end of the second dielectric waveguide and the direction in which the plasmon polarite is output from the end of the Nth metal layer cross each other in the dielectric cladding, The first to Nth metal layers may be formed in the dielectric clad such that (N-1) gaps are formed between the metal layers.

According to one embodiment, the plasmonic waveguide comprises first to Nth metal layers,

Wherein the first to Nth metal layers are on the same plane,

Wherein a direction in which light is incident from the end of the second dielectric waveguide to the first metal layer and a direction in which the plasmon polariton is output from the end of the Nth metal layer are parallel to each other while being spaced apart from each other in the dielectric cladding, The first to Nth metal layers may be formed in the dielectric clad so that (N-1) gaps are formed between the first to Nth metal layers.

According to another aspect of the present invention, there is provided a method for separating a light plasmon,

Introducing light into the input optical waveguide formed in the dielectric clad;

A step of guiding a part of the light branched along the first dielectric optical waveguide formed in the dielectric clad to the output optical waveguide so as to be branched from the input optical waveguide and extending to the output optical waveguide and outputting the part of the light branched from the output optical waveguide; And

Directing a remaining portion of the diverging light along a second dielectric optical waveguide branching at the input optical waveguide and being formed in the dielectric cladding shorter than the first dielectric optical waveguide;

Introducing a remaining portion of the branched light at the end of the second dielectric optical waveguide into a plasmonic waveguide formed of at least one metal layer formed in contact with the end of the second dielectric optical waveguide in the dielectric clad; And

And inducing a surface plasmon polariton excited by the plasmonic waveguide along the surface of the at least one metal layer of the plasmonic waveguide by incidence of the remaining portion of the branched light.

According to one embodiment, the step of directing the surface plasmon polariton comprises:

In the case where the plasmonic waveguide includes the first to Nth metal layers formed so as to have a gap therebetween, it is preferable that the surface plasmon polariton jumps in a gap in one metal layer, The surface plasmon polariton may be different from the direction of the surface plasmon polariton.

According to another aspect of the present invention, there is provided a method of forming an optical plasmon separation device,

Forming a first dielectric optical waveguide in the dielectric clad so as to extend from the input optical waveguide to the output optical waveguide;

Forming a second dielectric optical waveguide in the dielectric clad, the second dielectric optical waveguide being branched from the input optical waveguide and shorter than the first dielectric optical waveguide; And

And forming a plasmonic waveguide in the dielectric clad, the plasmonic waveguide being formed of at least one metal layer formed so as to be in contact with an end of the second dielectric optical waveguide.

According to an embodiment, the step of forming the plasmonic waveguide includes:

The first to Nth metal layers on the same plane are arranged such that a direction in which light is incident from the end of the second dielectric waveguide to the first metal layer and a direction in which the plasmon polariton is output from the end of the Nth metal layer intersect each other in the dielectric cladding And (N-1) gaps are formed between the first to N-th metal layers.

According to an embodiment, the step of forming the plasmonic waveguide comprises:

The first to Nth metal layers on the same plane are arranged such that the direction in which light is incident on the first metal layer from the end of the second dielectric waveguide and the direction in which the plasmon polariton is output from the end of the Nth metal layer are spaced apart from each other in the dielectric cladding And (N-1) gaps are formed between the first to N-th metal layers, in the dielectric cladding.

According to the optical plasmon separation apparatus and method of the present invention, a surface plasmon polariton (SPP) having information of an optical signal from an optical signal can be separated.

According to the optical plasmon separation apparatus and method of the present invention, it is possible to provide the optical plasmon separation apparatus having a relatively small size as compared with the optical separator.

The effects of the present invention are not limited to those mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the following description.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a conceptual diagram illustrating exemplary plasmonic waveguide structures in an optical plasmon separation apparatus according to an embodiment of the present invention; FIG.
2 is a conceptual diagram illustrating exemplary surface plasmon polariton modes in the optical plasmon separation apparatus according to an embodiment of the present invention.
3 is a conceptual diagram illustrating a plasmonic waveguide formed of a discontinuous metal layer separated by a gap in the optical plasmon separator according to an embodiment of the present invention.
4 is a conceptual diagram illustrating an optical plasmon separation apparatus according to an embodiment of the present invention.
5 is a conceptual diagram illustrating an optical plasmon separation apparatus according to another embodiment of the present invention.
6 is a conceptual diagram illustrating an optical plasmon separation apparatus according to another embodiment of the present invention.
7 is a flowchart illustrating an optical plasmon separation method according to embodiments of the present invention.
8 is a flowchart illustrating a method of forming the optical plasmon separation device according to the embodiments of the present invention.

For the embodiments of the invention disclosed herein, specific structural and functional descriptions are set forth for the purpose of describing an embodiment of the invention only, and it is to be understood that the embodiments of the invention may be practiced in various forms, The present invention should not be construed as limited to the embodiments described in Figs.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The same reference numerals are used for the same constituent elements in the drawings and redundant explanations for the same constituent elements are omitted.

Before describing the plasmonic waveguide, it is necessary to explain the waveguide of the surface plasmon polariton (SPP).

In the following description, a mode refers to a surface plasmon polariton (SPP) or existing forms of light that may exist depending on the electromagnetic characteristics of a given waveguide, or a surface plasmon polariton or light present in such form. A signal means SPP or light processed to have predetermined information.

FIG. 1 is a conceptual diagram illustrating schematically the structures of a plasmonic waveguide that can be used in the optical plasmon separation apparatus according to an embodiment of the present invention. FIG. And surface plasmon polariton modes.

Since the wave vector of the surface plasmon polariton (SPP) mode is generally larger than the wavenumber vector of the electromagnetic wave transmitted by the peripheral dielectric material, the SPP mode is an electromagnetic wave confined in the near region of the metal surface, and the SPP waveguide is a metal- Dimensional plane waveguide having a boundary surface as a core can be electromagnetically analyzed.

However, since the electric field of the SPP mode propagating in the general shape metal-dielectric interface exists to a considerable depth in the metal, the propagation loss is very large. Therefore, the traveling distance of the SPP mode in the visible light band is as short as several tens of micrometers.

However, if the metal is made into a very thin thin film of several tens of nanometers and the two SPPs are spatially overlapped on both surfaces of the metal thin film, the propagation distance of the SPP mode can theoretically increase infinitely.

In general, a nano plasmonic integrated circuit (NPIC), or a plasmonic device, is considered to be a plasmonic waveguide including a metal thin film in the form of a rectangular strip and a dielectric layer surrounding the metal thin film in consideration of a lithography process, Structure.

The structure of such a plasmonic waveguide can be largely classified into three structures: an insulator-metal-insulator (IMI) structure in which a metal thin film is formed, and a bimetal metal-insulator-metal (IMIMI) structure, and a thick metal-insulator-metal (MIM) structure that forms thick metal lines very closely and parallel.

Furthermore, it is possible to combine plasmonic waveguides of these three structures, for example, waveguides of a complex structure such as an IMI-IMIMI structure or an MIM-IMIMI structure.

The SPP coupling mode is a symmetric mode in which the distributions of the magnetic fields of two thin film surfaces are symmetrical with each other according to the distribution of the magnetic field on the two surfaces of the metal thin film and an asymmetric mode -symmetric mode).

Especially, the symmetric mode propagates most of the energy of the mode on the peripheral dielectric rather than the inside of the metal thin film, so the loss of metal is small and the propagation loss is greatly reduced. The mode that can propagate to long distance including this symmetric mode is called long range SPP (Long Range SPP, LRSPP) mode.

Even in the asymmetric mode, since the energy of the SPP mode propagates on the core dielectric mainly in the specific waveguide structure, the propagation loss is likewise very small and can be transmitted to a long distance.

On the other hand, in the IMI structure waveguide, it is known that excitation of long-range SPP exists only when the difference in dielectric constant between the two dielectric layers on both interfaces of the metal thin film is almost equal to or less than 10 ^ -4.

In the case of the IMIMI structure waveguide, the long-range SPP can be excited even if the dielectric constant of the core dielectric layer between the two metal thin films and the cladding layer outside the respective metal thin films is different, and the thickness and permittivity of the core dielectric layer can be controlled, It is known that the propagation loss, the effective refractive index, and the distribution of the mode can be controlled.

In the case of the MIM structure waveguide, the characteristics of the SPP mode can be adjusted according to the dielectric constant, thickness and width of the core dielectric layer between the two thick metal layers.

The metal material for implementing the plasmonic waveguide may be selected from noble metals and transition metals.

The dielectric layer can be selected from the example silicon (Si), silicon dioxide (SiO _2), silicon nitride (Si ₃ N ₄₎ and polymer (Polymer), for example.

In Fig. 2, first, the IMI waveguide has two modes, i.e., s ₀ mode and a ₀ mode. The s ₀ mode is a symmetric mode. If the propagation loss is small and the metal waveguide has a sufficiently thin thickness, And can also be excited by direct coupling with the optical fiber (butt joint). However, the a ₀ mode is an asymmetric mode, and although the size of the mode can be less than the diffraction limit of light, the size is small, but the propagation loss is very large and it is difficult to be excited by the direct coupling with the optical fiber.

Next, in the MIM waveguide, the Gs ₀ mode and the Ga ₀ mode are possible. Where G denotes the dielectric gap between the thick metal layers, which is different from the gap referred to in the remainder of the present invention.

In the case of the Gs ₀ mode, a magnetic field is formed symmetrically around the midplane of the core dielectric layer of the MIM waveguide so that the mode size is determined by the core dielectric layer thickness and width between the two metal layers. A mode having a size can be formed. Furthermore, since the SPP mode is guided along the core dielectric layer, the propagation loss is very small as compared with the asymmetric mode of the IMI waveguide, thereby enabling a large-scale highly integrated device.

In the case of IMIMI waveguide, each s ₀ mode is Ss ₀ mode, two metal films each s ₀ mode As ₀ mode, each of the a ₀ mode, two metal thin film to be formed into the asymmetrical type which is formed symmetrically on both the metal thin film Sa is the mode _0, each of the a ₀ mode, two metal thin film is formed in a symmetric mode ₀ Aa formed in asymmetric possible.

Among these modes, the Ss ₀ mode has a slightly smaller mode size and a larger propagation loss than the I ₀ s ₀ mode. s ₀ mode and Ss ₀ mode is equal to the shape of the magnetic field in the cladding layer it is advantageous for the coupling to each other.

Sa ₀ mode has a similar mode size and propagation loss and Gs ₀ mode of the MIM waveguide.

In the case of the As ₀ mode and the Aa ₀ mode in which the magnetic fields are asymmetrically distributed, although it can form a very small mode, the propagation loss is very large and is not suitable.

Therefore, in the remainder of this specification, unless specifically stated otherwise, the SPP mode can be applied to the structure of the waveguide being described in the s ₀ mode, the Gs ₀ mode, the Ss ₀ mode, and the Sa ₀ mode with small mode size and small propagation loss Can be understood as meaning a more advantageous mode.

3 is a conceptual diagram illustrating a plasmonic waveguide formed of a discontinuous metal layer separated by a gap in the optical plasmon separator according to an embodiment of the present invention.

Referring to FIG. 3, a plasmonic waveguide having a discontinuous IMI waveguide in which a gap exists in a waveguide of a single metal thin film (IMI) structure is illustrated.

Typically, SPP is an electromagnetic wave propagating along a metal-dielectric interface and is highly linear, making it difficult to control direction or intensity as desired. Although the SPP is an electromagnetic wave, which is described by Maxwell's equation as in electromagnetic, it can be controlled with refraction or reflection by using an optical material. However, optical materials are difficult to be integrated together with the plasmonic waveguide, and even optical materials having variable physical properties that can be used for switching and the like are not practical because of excessive power required for property change.

On the other hand, the plasmonic waveguides having discontinuous metal layers in the optical plasmon separation device of the present invention have a gap in the middle of the extending direction of the metal layers and different directions of extension of the metal layers on both sides of the gap, can do.

For example, the discontinuous IMI plasmonic waveguide 30 includes a first metal layer 31 having a width W1 and a first length di and starting from an input position, a first metal layer 31 having a width Wo, And a second metal layer 32 of a long strip shape.

A pair of first metal surfaces of the first metal layer 31 are in contact with the dielectric cladding 33 so that a surface plasmon polariton (SPP) in a symmetric or asymmetric mode can propagate and form a pair of first metal- .

When the TM polarized photon is incident on the input position Xi of the first metal layer 31, that is, when the polarized light is incident such that a magnetic field is formed parallel to the first metal-dielectric interfaces of the first metal layer 31 , The surface plasmon polariton propagates along the first metal-dielectric interfaces between the first metal layer 31 and the dielectric cladding 33 in a symmetric mode (s ₀ ). To this end, the dielectric cladding 33 may have a thickness such that the magnetic field of the surface plasmon polariton can be properly formed in the symmetrical mode (s ₀ ) and the metal layer can be physically or chemically protected.

The schematic diagram superimposed on the first and second metal layers 31 and 32 symbolizes the coupling mode SPP along the waveguide, which is based on the magnetic field distribution of the coupling mode SPP. Combined Mode The arrows in front of the SPP indicate the direction of travel of the SPP.

The gap 34 is present from the input start position to the gap end position where the second metal layer 32 starts, starting from the gap start position at which the first metal layer 31 is made to have a length of the first length di from the input position, And is filled with a dielectric by a gap length dc which is the distance between the gap start position and the gap end position.

A pair of second metal surfaces of the second metal layer 32 are also in contact with the dielectric cladding 33 to form a pair of second metal-dielectric interfaces so that the surface plasmon polariton of the symmetric or asymmetric mode can propagate do.

Next, the phenomenon occurring in the gap 34 will be examined. When the coupling mode SPP that has advanced along the surface of the first metal layer 31 reaches the gap starting position of the gap 34, a TM similar to the SPP is formed at the gap end position of the second metal layer 32 by the electromagnetic wave of the SPP. The electromagnetic wave of the mode is excited.

It appears as if SPP, a pseudo-particle, appears again in the second metal layer 32, starting at the gap end position, across the gap 34 passing through the dielectric material filled in the gap 34 region.

TM mode electromagnetic waves excited in the second metal layer 32 by leaping through the gap 34 continue to propagate along the pair of second metal-dielectric interfaces of the second metal layer 32.

Although the exemplary first and second metal layers 31 and 32 of FIG. 3 are in the form of "- -" having the same extending direction on the same plane, the extending direction of the second metal layer 32 Even if the second metal layer 32 is obliquely oblique as in the form of " _ / ", the SPP leaks the gap 34 from the first metal layer 31, even if it does not coincide with the extending direction of the first metal layer 31 And is excited by the second metal layer 32 placed obliquely.

The SPP once excited in the second metal layer 32 propagates along the second metal-dielectric interfaces. Since the extending direction of the second metal layer 32 is different from the extending direction of the first metal layer 31, this is similar to changing the traveling direction of the SPP.

If another metal layer is located at the end of the second metal layer 32 with a gap and the extending direction of the metal layer is different from the extending direction of the second metal layer 32, the traveling direction of the SPP is also switched.

On the other hand, if splitting the SPP mode into two with a continuous Y-shaped metal layer without gaps, a very long Y-shaped metal layer is required due to the linearity of the SPP mode.

4 is a conceptual diagram illustrating an optical plasmon separation apparatus according to an embodiment of the present invention.

4, the optical plasmon separation apparatus 40 includes a dielectric clad 41, an input optical waveguide 42, an output optical waveguide 43, a first dielectric optical waveguide 44, a second dielectric optical waveguide 45 ) And a plasmonic waveguide (46).

The dielectric cladding 41 can ensure the propagation of light through the optical waveguides 42, 43, 44 and 45 in accordance with optical properties such as total internal reflection with respect to the optical waveguides 42, 43, 44 and 45, 43, 44, 45 and the plasmonic waveguide 46 of the plasma optical waveguide 46 of the plasma optical waveguide 46 of the plasma optical waveguide 46, .

The first dielectric optical waveguide 44 may be formed in the dielectric clad 41 so as to extend from the input optical waveguide 42 to the output optical waveguide 43.

The input optical waveguide 42 and the output optical waveguide 43 may be formed to be compatible with, for example, PLC (Planar Light Circuit) optical elements or optical fibers.

The input optical waveguide 42 is formed in the dielectric clad 41 to have a predetermined length and is formed so that the first and second dielectric optical waveguides 44 and 45 are branched at the end of the input optical waveguide 42 in a Y- do.

The second dielectric optical waveguide 45 is branched into the dielectric clad 41 at the input optical waveguide 42 and is formed shorter than the first dielectric optical waveguide 44.

The plasmonic waveguide 46 may be composed of at least one metal layer 461 formed in the dielectric clad 41 so as to be in contact with the end of the second dielectric optical waveguide 45.

Typically, a PLC splitter can output branched optical signals at intervals of about 125 μm. Since most PLC optical devices or devices are designed to these dimensions, the optical plasmon separation device of the present invention can output optical signals and SPP signals to be compatible with these dimensions.

5 is a conceptual diagram illustrating an optical plasmon separation apparatus according to another embodiment of the present invention.

5 is substantially similar to the optical plasmon separator 40 of FIG. 4, except that the plasmonic waveguide 56 has at least two For example, first to Nth metal layers 561 to 564, for example.

At this time, extending directions of some metal layers of the first to Nth metal layers 561 to 564 may not be parallel to each other.

In particular, the extension directions of some metal layers of the first to Nth metal layers 561 to 564 may be at an acute angle with each other.

More specifically, the direction in which light is incident from the end of the second dielectric waveguide 45 to the first metal layer 561 and the direction in which the plasmon polarite is output to the outside from the end of the Nth metal layer 564 may cross each other And (N-1) gaps may be formed between the first to Nth metal layers 561 to 564.

The optical plasmon separator 50 of FIG. 5 can separate and transmit the SPP signal in the traveling direction perpendicular to the traveling direction of the optical signal input to the original input optical waveguide 42.

If the optical plasmon separator 50 of FIG. 5 ignores the optical signal output to the output optical waveguide 43, the optical plasmon separator 50 of FIG. 5 may reduce the traveling direction of the input optical signal by 90 degrees SPP < / RTI > signal.

6 is a conceptual diagram illustrating an optical plasmon separation apparatus according to another embodiment of the present invention.

The optical plasmon separator 60 of FIG. 6 is substantially similar to the optical plasmon separator 40 of FIG. 4, except that the plasmonic waveguide 66 has at least two For example, first to Nth metal layers 661 to 664, for example.

More specifically, the direction in which the light is incident on the first metal layer 561 from the end of the second dielectric waveguide 45 and the direction in which the plasmon polariton is output from the end of the Nth metal layer 564 are spaced apart from each other And (N-1) gaps may be formed between the first to Nth metal layers 561 to 564.

The optical plasmon separator 60 of FIG. 6 can separate and transmit the optical signal and the SPP signal in the traveling direction and the desired width of the optical signal incident on the original input optical waveguide 42.

7 is a flowchart illustrating an optical plasmon separation method according to embodiments of the present invention.

Referring to FIG. 7, the optical plasmon separation method may start from the step of inputting an optical signal to the input optical waveguide 42 formed in the dielectric clad 41 in step S71.

A part of the optical signal branched along the first dielectric optical waveguide 44 formed in the dielectric clad 41 is branched at the input optical waveguide 42 and extended to the output optical waveguide 43 at step S72, The branched optical signal can be outputted from the output optical waveguide 43 by guiding it to the optical waveguide 43. [

In step S73, along the second dielectric optical waveguide 45 branched at the input optical waveguide 42 and formed in the dielectric clad 41 shorter than the first dielectric optical waveguide 44, Some can be induced.

The plasma optical waveguide 46 composed of at least one metal layer 461 formed in contact with the end of the second dielectric optical waveguide 45 is formed in the dielectric clad 41 in the step S74, The remaining part of the optical signal branched at the end of the optical fiber 45 may be incident.

In step S75, the surface plasmon polariton excited by the plasmon waveguide 46 by the incidence of the remaining part of the branched optical signal is applied to the surface of at least one metal layer 461 constituting the plasmonic waveguide 46 .

Accordingly, the optical plasma separation method according to the present invention can separate an incident optical signal into an optical signal and an SPP signal.

According to the embodiment, in the case where the plasmonic waveguide 56 includes the first to Nth metal layers formed so that the plasmonic waveguide has a gap therebetween, the surface plasmon polariton 56, And jumping the gap in one metal layer to induce the surface plasmon polariton so that the traveling direction after excitation in the next metal layer is different from the traveling direction in the previous metal layer.

8 is a flowchart illustrating a method of forming an optical plasmon separation apparatus according to embodiments of the present invention.

8, a method of forming a photoplasmon separation apparatus according to an embodiment of the present invention includes the steps of: forming an output optical waveguide 43 in the dielectric clad 41, branched at the input optical waveguide 42, The first dielectric optical waveguide 44 may be formed so as to extend to the first dielectric optical waveguide 44. [

Subsequently, in step S82, for example, the second dielectric optical waveguide 45 may be formed in the dielectric clad 41, which is branched from the input optical waveguide 42 and shorter than the first dielectric optical waveguide 44 .

Next, in step S83, for example, a plasmonic waveguide 46 is formed in the dielectric clad 41, which is composed of at least one metal layer 461 formed so as to be in contact with the end of the second dielectric optical waveguide 45 can do.

According to the embodiment, the step of forming the plasmon waveguide of step S83 includes the steps of: forming first to Nth metal layers 561 to 564 on the same plane as the plasmon waveguide 56 of FIG. 5; The direction in which the optical signal is incident on the first metal layer 561 from the end of the dielectric waveguide 45 and the direction in which the plasmon polariton is output from the end of the Nth metal layer 564 cross each other, (N-1) gaps may be formed between the metal layers 561 to 564 in the dielectric clad 41. [

In another embodiment, the step of forming the plasmonic waveguide of step S83 includes the step of forming first to Nth metal layers 661 to 664 on the same plane as the plasmonic waveguide 66 of Fig. 6, 2 parallel to the first metal layer 661 at the end of the second dielectric waveguide 45 and to the outside of the Nth metal layer 664 at the end of the Nth metal layer 664, (N-1) gaps are formed between the first to N-th metal layers 661 to 664 in the dielectric clad 41. [

It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. It will be understood that variations and specific embodiments which may occur to those skilled in the art are included within the scope of the present invention.

30 Discontinuous IMI Waveguide Plasmonics
31 First metal layer
32 second metal layer
33 dielectric clad
34 Clearance
40, 50, 60 optical plasmon separator
41 dielectric clad
42 input optical waveguide
43 output optical waveguide
44 first dielectric optical waveguide
45 second dielectric optical waveguide
46, 56, 66 Plasmonic waveguides
461, 561, 562, 563, 564, 661, 662, 663, 664 metal layers

Claims (11)

A first dielectric optical waveguide formed in the dielectric clad so as to extend from the input optical waveguide to the output optical waveguide;
A second dielectric optical waveguide branched from the input optical waveguide and shorter than the first dielectric optical waveguide, in the dielectric clad; And
And at least one metal layer formed in the dielectric clad so as to be in contact with an end of the second dielectric optical waveguide,
A part of the light incident on the input optical waveguide branches to the first dielectric optical waveguide and is output to the outside through the output optical waveguide,
The remaining part of the light incident on the input optical waveguide is branched into the second dielectric optical waveguide, then excites the surface plasmon polariton in the plasmonic waveguide, and the excited surface plasmon polariton is output to the outside through the plasmonic waveguide The optical plasmon separation device comprising: The plasma display device according to claim 1, wherein at least one metal layer of the plasmonic waveguide
And at least two metal layers formed discontinuously with a gap in the dielectric cladding. The apparatus of claim 2, wherein the extending directions of some metal layers of the at least two metal layers are not parallel to each other. 3. The apparatus of claim 2, wherein the extending directions of the at least two metal layers and some of the metal layers form an acute angle with respect to each other. The plasma display device according to claim 2, wherein the plasmonic waveguide includes first to Nth metal layers,
Wherein the first to Nth metal layers are on the same plane,
The direction in which light is incident on the first metal layer from the end of the second dielectric waveguide and the direction in which the plasmon polarite is output from the end of the Nth metal layer cross each other in the dielectric cladding, Wherein the first to Nth metal layers are formed in the dielectric cladding so that (N-1) gaps are formed between the metal layers. The plasma display device according to claim 2, wherein the plasmonic waveguide includes first to Nth metal layers,
Wherein the first to Nth metal layers are on the same plane,
Wherein a direction in which light is incident from the end of the second dielectric waveguide to the first metal layer and a direction in which the plasmon polariton is output from the end of the Nth metal layer are parallel to each other while being spaced apart from each other in the dielectric cladding, Wherein the first to Nth metal layers are formed in the dielectric cladding so that (N-1) gaps are formed between the first to Nth metal layers. Introducing light into the input optical waveguide formed in the dielectric clad;
A step of guiding a part of the light branched along the first dielectric optical waveguide formed in the dielectric clad to the output optical waveguide so as to be branched from the input optical waveguide and extending to the output optical waveguide and outputting the part of the light branched from the output optical waveguide; And
Directing a remaining portion of the diverging light along a second dielectric optical waveguide branching at the input optical waveguide and being formed in the dielectric cladding shorter than the first dielectric optical waveguide;
Introducing a remaining portion of the branched light at the end of the second dielectric optical waveguide into a plasmonic waveguide formed of at least one metal layer formed in contact with the end of the second dielectric optical waveguide in the dielectric clad; And
And guiding the surface plasmon polariton excited by the plasmonic waveguide along the surface of at least one metal layer of the plasmonic waveguide by incidence of the remaining portion of the branched light. The method of claim 7, wherein the step of directing the surface plasmon polariton comprises:
In the case where the plasmonic waveguide includes the first to Nth metal layers formed so as to have a gap therebetween, it is preferable that the surface plasmon polariton jumps in a gap in one metal layer, Wherein the surface plasmon polarity is different from the direction of the surface plasmon polarity. Forming a first dielectric optical waveguide in the dielectric clad so as to extend from the input optical waveguide to the output optical waveguide;
Forming a second dielectric optical waveguide in the dielectric clad, the second dielectric optical waveguide being branched from the input optical waveguide and shorter than the first dielectric optical waveguide; And
And forming a plasmonic waveguide in the dielectric clad, the plasmonic waveguide being formed of at least one metal layer formed in contact with an end of the second dielectric optical waveguide. The method of claim 9, wherein forming the plasmonic waveguide comprises:
The first to Nth metal layers on the same plane are arranged such that the direction in which light is incident from the end of the second dielectric waveguide to the first metal layer and the direction of the plasmon polarite in the end of the Nth metal layer cross each other in the dielectric cladding And (N-1) gaps are formed between the first to N-th metal layers in the dielectric cladding layer. The method of claim 9, wherein forming the plasmonic waveguide comprises:
The first to Nth metal layers on the same plane are parallel to each other with the plasmon polaritons being spaced apart from each other in the dielectric clad in the direction in which light is incident on the first metal layer from the end of the second dielectric waveguide and the end of the Nth metal layer And (N-1) gaps are formed between the first to Nth metal layers, in the dielectric cladding.

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