Integrated waveguide and light field control method thereof

Abstract

The invention provides an integrated waveguide and a light field control method thereof. The integrated waveguide comprises a semiconductor material layer and metal material layers attached to the surfaces of the two sides of the semiconductor material layer. A plurality of gap regions are embedded in the semiconductor material layer; and the gap regions are periodically and symmetrically arranged on two side edges in the semiconductor material layer. The integrated waveguide provided by the invention takes the semiconductor material layer as the core part of the waveguide and is used for providing a light transmission channel, periodic gap areas are designed on the left and right sides in the integrated waveguide so as to adjust the transmission mode of light waves, and the metal material layers on the two sides of the semiconductor material layer are utilized to realize the isolation of adjacent waveguides, so that the transmission efficiency is improved. Therefore, the conflict between the light field binding capability and the transmission distance in the prior art is effectively solved, the balance and optimization among the light field binding capability, the integration level and the transmission distance are realized, and the method is suitable for the application of large-scale photon integration.

Description

Technical Field

[0001] The present invention relates to the technical field of optical waveguides, and particularly to an integrated waveguide and a method for controlling its optical field. Background Art

[0002] In the prior art, in order to prevent waveguide signals from crosstalking to adjacent waveguides, it is necessary to set a waveguide core-core spacing that exceeds multiple wavelengths. Although high refractive index difference dielectric optical waveguides basically meet the requirements of sub-wavelength mode field confinement ability and low-loss transmission distance of more than millimeter level, they cannot meet the two requirements of low signal crosstalk and compact large-angle turning under sub-wavelength waveguide spacing.

[0003] Photonic crystals form defect modes in the photonic bandgap by introducing line defects, thereby confining light waves to transmit in the line defects. However, in order to avoid the generation of radiation modes and eliminate signal crosstalk between adjacent integrated waveguides, photonic crystals require multiple periodic structures, which greatly limits the integration density of photonic crystal waveguides and cannot meet all the requirements of large-scale photonic integration at the same time.

[0004] Therefore, the prior art needs further improvement. Summary of the Invention

[0005] In view of the above deficiencies in the prior art, the purpose of the present invention is to provide an integrated waveguide and a method for controlling its optical field, so as to solve the defect that the optical waveguides in the prior art cannot achieve both long-range transmission and sub-wavelength mode field confinement performance.

[0006] In a first aspect, the present invention provides an integrated waveguide, which includes: a semiconductor material layer and metal material layers attached to both side surfaces of the semiconductor material layer; a plurality of void regions are embedded in the semiconductor material layer; the void regions are periodically and symmetrically arranged on two side edges within the semiconductor material layer.

[0007] Optionally, the void regions are periodically arranged in two columns, and each void region in the two columns of void regions is evenly and symmetrically distributed on both sides within the semiconductor material layer.

[0008] Optionally, the refractive index of the semiconductor material layer is greater than 2.5.

[0009] Optionally, the material of the semiconductor material layer is a semiconductor material without light absorption.

[0010] Optionally, the material of the semiconductor material layer is silicon dielectric; the material of the metal material layer is a noble metal or aluminum.

[0011] Optionally, the shapes of the semiconductor material layer, the metal material layer, and the integrated waveguide after the combination of the semiconductor material layer and the metal material layer are all in the shape of a cuboid or a rounded cuboid.

[0012] Optionally, the shape of the void region is a cube shape or a rounded cuboid shape.

[0013] Optionally, the width of the semiconductor material layer is 0.35 to 0.45 times the central wavelength, the width range of the metal material layer is 50 to 60 nm, and the side length of the void region is 0.95 to 0.15 times the central wavelength.

[0014] Optionally, the lateral spacing between two symmetrically arranged void regions on the left and right is 0.15 - 0.2 times the central wavelength; the longitudinal period between two adjacent void regions above and below is 0.3 - 0.33 times the central wavelength.

[0015] In a second aspect, the present invention provides a method for controlling the optical field of an integrated waveguide, which is applied to the integrated waveguide described above;

[0016] Receiving an input optical wave and forming a transmission channel for the optical wave in the semiconductor material layer; adjusting the propagation mode of the optical wave transmitted in the transmission channel by using a plurality of void regions, and constraining the transmission boundary of the optical wave transmitted in the received transmission channel by using the metal material layer, so as to realize the control of the optical field of the input optical wave.

[0017] Advantageous effects:

[0018] The present invention provides an integrated waveguide and a method for controlling its optical field. The integrated waveguide includes: a semiconductor material layer and metal material layers attached to both side surfaces of the semiconductor material layer; a plurality of void regions are embedded in the semiconductor material layer; the void regions are periodically and symmetrically arranged on two side edges in the semiconductor material layer. Since the integrated waveguide provided by the present invention takes the semiconductor material layer as the core part of the waveguide to provide a transmission channel for light, by designing periodically arranged void regions on its left and right sides to adjust the transmission mode of the optical wave, and at the same time using the metal material layers located on both sides of the semiconductor material layer to realize the isolation of adjacent waveguides, thus effectively solving the conflict between the optical field confinement ability and the transmission distance in the prior art, and achieving the balance and optimization among the optical field confinement ability, integration degree and transmission distance. It is applicable to the application of large-scale photon integration. Description of the Drawings

[0019] Figure 1 is a three-dimensional structural schematic diagram of the integrated waveguide provided by the present invention;

[0020] Figure 2 is a planar structural schematic diagram of the integrated waveguide provided by the present invention. Detailed Embodiments

[0021] To make the objectives, technical solutions and advantages of the present invention clearer and more explicit, the following further elaborates on the present invention with reference to the accompanying drawings and by way of examples. It should be understood that the specific examples described herein are only used to explain the present invention and are not intended to limit the present invention.

[0022] The light guiding mechanism of a conventional dielectric optical waveguide is based on the principle of total internal reflection inside the waveguide. At the interface between the thick high refractive index / low refractive index dielectrics, the light wave extends in the dielectric cladding in the form of an evanescent wave with a negative exponential decay up to several micrometers or more. To prevent waveguide signal crosstalk to adjacent waveguides, a waveguide core-core spacing exceeding several wavelength sizes must be set. Although the high refractive index difference dielectric optical waveguide basically meets the requirements of sub-wavelength mode field confinement ability and low loss for transmission distances above millimeter level, it cannot overcome the low signal crosstalk at sub-wavelength waveguide spacing and meet the requirements of large-angle turning transmission when the spacing is compact.

[0023] A waveguide using a photonic crystal as the medium utilizes the introduction of a line defect in the photonic crystal to form a defect mode in the photonic bandgap, thereby confining the light wave to transmit in the line defect. Through process improvement, the line defect bandgap type photonic crystal waveguide can have relatively low transmission loss. Using the photonic bandgap property, a large-angle direct turn of the photonic crystal waveguide can be obtained. However, since the lateral periodic air gaps or dielectric columns are an indispensable part of the two-dimensional photonic crystal, many columns of periodic structures are required to avoid the generation of radiation modes and eliminate signal crosstalk between adjacent integrated waveguides. Therefore, the width of the photonic crystal cladding is much larger than the wavelength order of magnitude, greatly limiting the integration density of the photonic crystal waveguide and unable to meet all the requirements of large-scale photonic integration simultaneously.

[0024] Surface plasmon polaritons can, in principle, provide a deep sub-wavelength mode field confinement ability with strong mode field confinement characteristics. In a metal-dielectric-metal (MDM) waveguide, a compact and efficient direct turn of the waveguide can be constructed. The surface plasmon polariton wavelength has various forms and can be divided into short-range surface plasmon optical waveguides and long-range surface plasmon optical waveguides. The short-range surface plasmon optical waveguide has an extremely strong optical field confinement ability at the sub-wavelength level, but the optical loss is also extremely high. Most of the energy is lost after transmitting several micrometers, making it impossible to achieve small-scale photonic integration and thus large-scale integration. Although the long-range surface plasmon optical waveguide has relatively low loss and a transmission distance above millimeter level, its optical field confinement ability is very weak, and the lateral optical field width exceeds the wavelength order of magnitude, resulting in a core-core waveguide spacing of several micrometers, which cannot meet the large-scale on-chip integration density. Therefore, neither the short-range surface plasmon optical waveguide nor the long-range surface plasmon optical waveguide can have both long-range transmission characteristics and sub-wavelength mode field confinement performance. This mutual restriction between the transmission distance and the optical field confinement performance has led to the problem that the practical application of the surface plasmon waveguide integration platform remains unsolved to date.

[0025] To overcome the above - mentioned deficiencies, this embodiment provides an integrated waveguide and its optical - field control method. The integrated waveguide is a metal - semiconductor material - metal structure, and periodic voids are provided in the semiconductor material layer. It uses the semiconductor material layer in the middle as the transmission channel for light waves, and uses the metal material layers on both sides of the semiconductor material layer to confine the light waves at the boundaries, achieving highly isolated coupling between adjacent waveguides, reducing the waveguide core - core pitch, and thus increasing the on - chip integration density. On the other hand, by designing a periodically arranged void region on the semiconductor material layer, the propagation mode is regulated through the photonic - bandgap effect, thereby realizing the efficient and low - loss propagation of light waves in the semiconductor material layer.

[0026] The following further elaborates in more detail on an integrated waveguide and its optical - field control method provided in this embodiment with reference to the accompanying drawings.

[0027] In a first aspect, the present invention provides an integrated waveguide, as Figure 1 shown, comprising: a semiconductor material layer 110 and metal material layers 120 attached to the two side surfaces of the semiconductor material layer 110; a plurality of void regions 130 are embedded in the semiconductor material layer 110; the void regions are periodically and symmetrically arranged on two side edges within the semiconductor material layer.

[0028] The integrated waveguide provided in this embodiment is a combination structure of metal - semiconductor material - metal, and the semiconductor material layer is located in the middle and belongs to the core component of the waveguide. The input light wave is transmitted into the semiconductor material layer, and the light wave is guided to propagate through the semiconductor material layer. Moreover, a plurality of void regions are embedded in the semiconductor material layer, and these void regions can effectively enhance the confinement mode of the optical field. The metal material layers designed on both side edges of the semiconductor material layer can achieve efficient isolation of adjacent waveguides, thereby greatly reducing the waveguide core - core pitch and significantly improving the on - chip integration density of the waveguide.

[0029] Specifically, the semiconductor material layer located in the middle of the integrated waveguide has a high refractive index, so it can provide a transmission channel for the input light wave and realize millimeter - scale long - range transmission of the light wave in the semiconductor material layer. Further, in one implementation, the semiconductor material used is a semiconductor material with no light absorption. Since a semiconductor material with no light absorption refers to a semiconductor material that has very weak light absorption or almost no light absorption in a certain spectral range, using a semiconductor material with no light absorption to fabricate the semiconductor material layer in this embodiment can minimize light loss, improve the transmission efficiency of light waves, and increase the transmission distance of light waves.

[0030] The void region within the semiconductor material regulates the propagation mode through the photonic bandgap effect. Since the void region has a periodic structure, this periodic structure can cause photons to be periodically modulated when propagating inside it. Since the void region is filled with air, an alternating distribution of high and low refractive indices is formed between the periodically distributed void regions and the semiconductor material layer where they are located. Due to the periodic arrangement of these regions, when photons are transmitted between air and the semiconductor material, the photons will be modulated by this periodic structure.

[0031] Furthermore, there is a specific frequency range in the periodic structure formed in the semiconductor material layer, called the photonic bandgap. Within this frequency range, the propagation of light is prohibited or severely restricted because when the frequency of the light wave falls within the photonic bandgap, the interaction between the photons and the periodic structure will cause the light wave to be scattered or refracted and unable to continue propagating. Therefore, by adjusting the structural parameters of the periodic structure, such as the side length of the void region (taking the shape of the void region as a square as an example), the width and position of the photonic bandgap can be changed, thereby achieving rotational reflection or scattering of light waves with specific frequencies.

[0032] In this embodiment, the metal material layer is a thin metal strip, which is closely attached to the left and right sides of the semiconductor material layer to receive the light waves reflected or refracted from the semiconductor material layer. Since metal has a very high conductivity in the optical frequency band, according to electromagnetic theory, when a light wave is incident on the metal surface, an induced current will be generated, and this induced current will generate a reflected wave, causing most of the incident electromagnetic waves to be reflected back. Therefore, metal can be regarded as a material with strong reflection characteristics for light waves. With the reflection characteristics of metal, the metal strip can be used as a boundary condition to constrain the propagation of the light field. When a light wave irradiates on the metal strip, due to the reflection characteristics of the metal, the light wave will be reflected back to the original semiconductor material layer, thereby forming a strong light field localization near the metal strip. This localization effect makes the light field have a high intensity near the metal strip and a low intensity in the region far from the metal strip. Therefore, the integrated waveguide disclosed in this embodiment constrains the boundary of the light field through the metal material layer to enhance the light field localization and suppress the radiation loss.

[0033] Furthermore, by modulating the periodic distribution position of the void region in the semiconductor material layer, the waveguide structure can exhibit an efficient large-angle direct turning ability within the C band. Even after a large-angle turn, the light field still maintains the fundamental mode transmission characteristics, and the transmission efficiency exceeds 95%. The integrated waveguide provided in this embodiment can effectively solve the conflict between the light field confinement ability and the transmission distance in the prior art, and achieves a reasonable balance and optimization among the light field confinement ability, integration degree, and transmission distance. Its design is particularly suitable for large-scale photon integration applications and can be widely used in fields such as optical communication, photonic chips, and high-performance sensors.

[0034] In specific implementation, the semiconductor material layer can be silicon, germanium, gallium arsenide, silicon dioxide, silicone composite material, and other semiconductor materials. Preferably, the material of the semiconductor material layer is silicon dielectric; the material of the metal material layer is noble metal or aluminum.

[0035] Furthermore, the void regions are periodically arranged in two columns, and each void region in the two columns of void regions is uniformly and symmetrically distributed on both sides within the semiconductor material layer. Combining Figure 2 As shown, there are two columns of periodically arranged void regions, and these two columnar structures are respectively located on the left and right sides of the semiconductor material layer. Each void region is in the shape of a small rectangular unit.

[0036] It should be emphasized that in a specific embodiment, the arrangement structure of the void regions is in two columns and is symmetrically distributed on the two side edges within the semiconductor material layer. Since there is only one column of void regions on each side edge, when the light wave in the semiconductor material layer diverges laterally to the void regions, a part of the light is reflected back to the transmission path within the semiconductor material layer by the voids, and the other part diverges to reach the surface of the metal material and then is reflected back into the semiconductor material layer. Due to the integrated waveguide disclosed in this embodiment, with only one column of void regions designed on one side, it can solve the problem that when the number of rows and columns of the periodic structure is large, the lateral size of the waveguide increases, resulting in a decrease in the waveguide integration degree.

[0037] In one implementation, the shapes of the semiconductor material layer, the metal material layer, and the integrated waveguide formed by combining the semiconductor material layer and the metal material layer are all in the shape of a cuboid or a rounded cuboid. Since the integrated waveguide and each component of the integrated waveguide are all in the cuboid structure, this waveguide has the advantages of simple structure and easy manufacturing. And the cuboid waveguide often has a relatively wide frequency band range and stable transmission performance, so it has strong wide-band working ability. In addition, the cuboid waveguide also has low-loss characteristics and quantifiable shielding performance, ensuring the stable transmission of signals, and the cuboid waveguide is also easy to integrate and expand, suitable for various environments.

[0038] Furthermore, in order to realize the regulation of the propagation mode of the light wave in the semiconductor material layer, the shape of each void region can be a cube shape or a rounded cuboid shape. Since when the void region is designed to be in the cube shape or the rounded cuboid shape, it is not only easy to manufacture, but also the cuboid structure has a specific photonic bandgap structure, and the structural parameters and refractive index distribution are easy to optimize and adjust, so it has a relatively wide application scenario. In practical applications, it can be designed and optimized according to needs.

[0039] In order to realize a smaller light field and achieve large-scale photon integration, based on the premise that the higher the refractive index, the smaller the lateral light field size, in specific implementation, the refractive index of the semiconductor material layer is set to be greater than 2.5.

[0040] The present invention provides a metal-periodic gap boundary integrated waveguide. Compared with existing dielectric waveguides such as silicon and photonic crystal waveguide technologies, the integrated waveguide provided by the present invention has stronger field confinement capability, smaller waveguide spacing, lower signal crosstalk and longer transmission distance, and therefore has a greater degree of integration. Compared with metal surface plasmon waveguides, it has a loss that is several orders of magnitude lower, and thus has a transmission length of more than millimeters. This solves the current problem of the serious trade-off between field confinement performance and transmission distance, achieves a reasonable balance and optimization between field confinement performance, integration and transmission distance, and meets the needs of large-scale photonic integration.

[0041] The waveguide provided in this embodiment is further described in detail below using the light guiding mechanism of the integrated waveguide.

[0042] First, the light-guiding mechanism of the integrated waveguide can be analyzed by the following method. First, the gap areas on both sides of the left and right boundaries of the waveguide are divided into two rows of periodic small rectangular units. Since the waveguide has a periodic structure in the transmission direction, a waveguide structure of a periodic unit can be considered. Then, using the equivalent refractive index method, the area-weighted average value of the refractive index of each small rectangular unit is calculated according to the area filling ratio of different dielectric materials, thereby simplifying the integrated waveguide to a metal-low refractive index medium-high refractive index medium-low refractive index medium-metal waveguide model. According to the waveguide optics theory: 1) The transverse electric field mode of the waveguide light field is directly solved to obtain the light field distribution function of each region; 2) Using the boundary continuity condition, the light field function of each region is combined to obtain the characteristic equation of its light field mode; 3) Solving the characteristic equation gives the waveguide mode refractive index.

[0043] Table 1. Transmission efficiency of light in integrated waveguides in the wavelength range of 1.45 to 1.80 μm.

[0044]

[0045] The optical transmission characteristics of the waveguide mainly include: transmission distance, mode field size, working bandwidth and comprehensive performance factor. By comparing with the imaginary part of the fundamental mode refractive index of the traditional MDM waveguide with the same width, it is found that the transmission loss of the integrated waveguide model is more than 5 times smaller than that of the traditional metal waveguide. The analysis in Table 1 shows that the transmission efficiency of light in the integrated waveguide exceeds 99% in the wavelength range of 1.45 to 1.80 μm. It is proved that the introduction of (quasi) periodic gaps can effectively reduce the transmission loss of traditional metal waveguides, thereby achieving a centimeter-level optical transmission length.

[0046] Table 2. Comparison of the transmission distances between the integrated waveguide and the traditional MDM waveguide in the wavelength range of 1.45 - 1.80 μm.

[0047]

[0048] It can be seen from the analysis of Table 2 that the integrated waveguide has a larger working bandwidth. Especially in the C band and some S and L bands, the loss is the smallest and the transmission distance exceeds 1 cm. It can be seen that the role of the void area as an isolation buffer is most obvious near 1.55 μm. And by comparing the transmission distances of the integrated waveguide and the corresponding traditional MDM waveguide, it can be known that with the introduction of the periodic void area, the overall transmission distance has been greatly extended.

[0049] Analysis of the optical field confinement ability of the integrated waveguide: Since the integrated waveguide structure has periodicity in the transmission direction, its energy distribution also shows periodic characteristics identical to the void period. The optical field width between the void areas is always slightly larger than the optical field width between the two metal material layers on both sides. Relative to the wavelength in vacuum, its mode field width is in the sub-wavelength order. Therefore, due to the introduction of the periodic voids, the mode field width will also be "compressed" to a large extent, further reducing the transverse width of the mode field and also reducing the contact between the optical field and the metal, increasing the transmission distance. So both the mode field confinement ability and the transmission length are improved, thereby improving the figure of merit of the waveguide. The figure of merit is defined as: where L P and λ 0 are the transmission length and wavelength respectively, n eff is the equivalent refractive index, and w 0 is the mode field width. The longer the transmission distance of the waveguide, the more devices can be integrated in the transmission direction. Similarly, the smaller the transverse mode field width of the waveguide, the higher the integration density of the waveguide array. At a wavelength of 1.55 μm, the transmission length is 17 mm, the transverse mode field width is about 564 nm, and the equivalent refractive index calculated from the characteristic equation is 3.33. The figure of merit calculated from the above definition = 6×10 8 , which is two orders of magnitude higher than that of the long-range dielectric-loaded surface plasmon waveguide. At the same time, the transverse mode field width of the integrated waveguide is much smaller than the 1510 nm mode field width of the long-range dielectric-loaded surface plasmon waveguide. Therefore, the integrated waveguide provided in this embodiment has a higher integration degree.

[0050] Since whether large-angle direct turning can be achieved is crucial for whether the waveguide is suitable for large-scale photon integration. The analysis of the normalized spectral response of the integrated waveguide calculated by the finite-difference time-domain method shows that the optical path of the integrated waveguide can be efficiently bent near the C band. When the incident light wavelength is 1.55 μm, by simply adjusting the sizes and positions of several voids near the turning area, the transmission efficiencies of both 90° and 120° large-angle direct turning exceed 95%.

[0051] Photonic chips usually integrate a large number of parallel optical waveguides. In order to work without interference from each other, it is necessary to ensure that the waveguide core-core spacing exceeds a certain threshold interval, thereby effectively reducing the signal crosstalk between parallel integrated waveguides and obtaining a high waveguide isolation. If the transverse mode field of a waveguide is suppressed smaller and the penetration depth of the evanescent field through the photonic barrier is smaller, at the same core-core spacing, the mode field overlap between adjacent waveguides will be smaller, thereby obtaining a smaller coupling coefficient, increasing the waveguide isolation and coupling length. Since the mode field width of the integrated waveguide is between 511 nm and 564 nm and the skin depth of the metal is less than 20 nm, by reasonably designing the thickness of the adjacent metal material layers, the signal crosstalk caused by the evanescent field can be effectively reduced. The isolation between adjacent waveguides can be solved by the formula: I SO = 10×log(P 2 / P 1 ), where I SO is the waveguide isolation, and P 1 and P 2 are the powers of the channel waveguide and the output port of the adjacent waveguide respectively. This formula can be used to calculate and compare the variation relationship of the isolation of traditional waveguides and new waveguides with the core-core waveguide spacing of adjacent waveguides when the typical length is 100 μm.

[0052] Table 3. Data comparison between silicon-based SOI waveguides and integrated waveguides

[0053]

[0054] Table 3 compares the core-core waveguide spacing, isolation, and integration of typical silicon-based SOI waveguides and integrated waveguides. Under the conditions that the isolation of both the SOI waveguide and the integrated waveguide is 50 dB and the length is 100 μm, the core-core waveguide spacing of the silicon-based SOI waveguide must be not less than 2.8 μm, while the core-core spacing of the integrated waveguide provided in this embodiment can be not less than 1.1 μm. This spacing is less than the vacuum wavelength, so it can be called a sub-wavelength waveguide.

[0055] The total number of parallel integrated waveguides with high isolation (not less than 50 dB) per unit millimeter of transverse width is defined as the integration. Calculations show that the integration of the integrated waveguide > 875 / mm, and the integration of the SOI waveguide > 355 / mm. For the long-range dielectric-loaded surface plasmon waveguide, the waveguide width needs to be maintained at 4 - 6 μm to obtain a high isolation, and its integration is even lower. Through the above discussion and analysis, it can be seen that the integrated waveguide meets the basic requirements of large-scale photonic integration such as sub-wavelength mode field confinement ability, long-range transmission distance, low crosstalk characteristics under sub-wavelength waveguide spacing, and efficient and compact direct turning at corners, so it is worthy of application and promotion.

[0056] Combined withFigure 1 and Figure 2 As shown in Figure 2 , in order to achieve a better optical field control effect, the key parameters of the integrated waveguide provided in this embodiment include: the width w of the semiconductor material layer 1 (unit: nm) is 0.35 - 0.45 times the central wavelength, the width w of the metal material layer 2 (unit: nm) ranges from 50 to 60 nm, and the side length L (unit: nm) of the gap region is 0.95 - 0.15 times the central wavelength. The lateral spacing w 3 (unit: nm) between the two symmetric gap regions on the left and right is 0.15 - 0.2 times the central wavelength; the longitudinal period p between the two adjacent gap regions above and below is 0.3 - 0.33 times the central wavelength.

[0057] In the specific implementation, the material of the semiconductor material layer is set to silicon, and its width is 0.4 times the central wavelength. The material of the metal material layer is set to aluminum, and its width is not greater than 60 nm. The side length of the gap region is set to one-tenth of the central wavelength. The length of the lateral spacing is one-fifth of the central wavelength. The length of the longitudinal period is one-third of the central wavelength. Since silicon and aluminum are rich in reserves and low in cost, the integrated waveguide provided in this embodiment has a low manufacturing cost and can be widely promoted. Moreover, silicon and aluminum have excellent electrical properties, and at the same time have relatively stable physical and chemical properties, with high reliability, so that the integrated waveguide provided in this embodiment has good electrical, physical and chemical properties.

[0058] In the second aspect, the present invention provides an optical field control method for an integrated waveguide, which is applied to the integrated waveguide; the optical field control method specifically includes: receiving an input optical wave and forming a transmission channel for the optical wave in the semiconductor material layer; using a plurality of gap regions to adjust the propagation mode of the optical wave transmitted in the transmission channel, and using the metal material layer to constrain the transmission boundary of the optical wave transmitted in the received transmission channel, so as to achieve the optical field control of the input optical wave.

[0059] In the optical field control method of this embodiment, a silicon medium provides an optical wave propagation channel (high refractive index); the periodic gaps regulate the propagation mode through the multi-reflected sub-wave interference effect, and the metal material layer is used to enhance the optical field localization and suppress the radiation loss.

[0060] In the wavelength range of 1.45 - 1.80 μm, the transmission efficiency of light in the integrated waveguide exceeds 99%; in the C band and part of the S and L bands, the transmission distance exceeds 1 cm; the transmission efficiencies of 90° and 120° large-angle turns both exceed 95%. Therefore, the integrated waveguide provided in this embodiment can achieve a better optical wave transmission effect, and has both the optical field confinement ability and the long-distance transmission performance.

[0061] The integrated waveguide provided in this embodiment uses a thin metal region to highly isolate adjacent waveguides, reducing the coupling between waveguides; the core-to-core distance of the waveguide is reduced, increasing the on-chip integration density and supporting high-density integrated design. It is applicable to fields such as optical communication and photonic chips, and can provide a low-loss, long-distance, high-density waveguide solution for optical communication, as well as be suitable for the design of large-scale integrated circuits, including systems such as optical neural networks and optical computing, improving the functional density and performance of the chip.

[0062] Those skilled in the art will readily conceive of other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. The present invention is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of the present invention and include known common knowledge or conventional technical means in the technical field not disclosed in this application. The specification and examples are only regarded as exemplary, and the true scope and spirit of the present invention are pointed out by the following claims.

[0063] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or N embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0064] It can be understood that the above embodiments are exemplary and should not be construed as limitations on the present application. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present application.

Claims

1. An integrated waveguide, characterized in that: include: A semiconductor material layer and a metal material layer attached to both side surfaces of the semiconductor material layer; A plurality of void regions are embedded in the semiconductor material layer; The gap regions are periodically and symmetrically arranged on two sides of the semiconductor material layer.

2. The integrated waveguide according to claim 1, characterized in that The void regions are periodically arranged in two rows, and the void regions in the two rows are evenly and symmetrically distributed on both sides of the semiconductor material layer.

3. The integrated waveguide according to claim 1, characterized in that The refractive index of the semiconductor material layer is greater than 2.

5.

4. The integrated waveguide according to claim 1, characterized in that The semiconductor material layer is made of a semiconductor material that does not absorb light.

5. The integrated waveguide according to claim 1, characterized in that The material of the semiconductor material layer is silicon dielectric; the material of the metal material layer is noble metal or aluminum.

6. The integrated waveguide according to any one of claims 1 to 5, characterized in that: The shapes of the semiconductor material layer, the metal material layer, and the integrated waveguide formed by combining the semiconductor material layer and the metal material layer are all in the shape of a cuboid or a cuboid with rounded corners.

7. The integrated waveguide according to any one of claims 1 to 5, characterized in that: The shape of the gap area is a cube or a rounded rectangular parallelepiped.

8. The integrated waveguide according to claim 1, characterized in that The width of the semiconductor material layer is 0.35 to 0.45 times of the central wavelength, the width of the metal material layer is in the range of 50 to 60 nm, and the side length of the gap region is 0.95 to 0.15 times of the central wavelength.

9. The integrated waveguide according to claim 8, characterized in that The lateral spacing between the two bilaterally symmetrical gap regions is 0.15-0.2 times of the central wavelength; the longitudinal period between the two vertically adjacent gap regions is 0.3-0.33 times of the central wavelength.

10. A method for controlling a light field of an integrated waveguide, characterized in that: Applicable to an integrated waveguide as claimed in any one of claims 1 to 9; An input light wave is received and a transmission channel of the light wave is formed in the semiconductor material layer; a propagation mode of the light wave transmitted in the transmission channel is adjusted by using a plurality of gap regions, and a transmission boundary of the light wave transmitted in the received transmission channel is constrained by using a metal material layer, so as to realize light field control of the input light wave.

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