Power Regulation Unit of Asymmetric Composite Wave Chip Based on TCO Material

Abstract

The present invention discloses an asymmetric combiner / demultiplexer chip power adjustment unit based on TCO materials, which belongs to the technical field of optical elements, systems or instruments. The power adjustment unit is made of transparent conductive oxide material, including a waveguide layer, a transparent conductive oxide material layer, an oxide layer, and a metal layer, forming a plasma metal oxide semiconductor effect, and realizing dynamic adjustment of the transmittance of the asymmetric combiner / demultiplexer chip by applying an external voltage. The present invention is combined with a closed-loop feedback system to realize intelligent adjustment of the transmittance of the asymmetric combiner / demultiplexer chip according to different wavelengths, and then adjust the output power of each output waveguide, so that the operating wavelength of the asymmetric combiner / demultiplexer chip can cover the full band in the optical communication system, and realize the stable performance of the asymmetric combiner / demultiplexer chip with the non-uniform wavelength division function of the full band energy.

Description

Technical Field

[0001] The present invention discloses an asymmetric wave combiner / demultiplexer chip power adjustment unit based on TCO (Transparent Conducting Oxide) material, relates to optical communication and integrated optoelectronic device technology, and belongs to the technical field of optical elements, systems or instruments. Background Art

[0002] With the rapid development of 5G, big data, live video streaming, and artificial intelligence, data volumes on access and bearer networks are exploding, posing technical challenges for traditional access network transmission equipment. A popular approach is to apply transmission equipment previously used in backbone networks to access and bearer networks, a practice known as "coherent sinking." The main drawbacks of this approach are high cost, technical difficulty, and susceptibility to lightning interference. To effectively increase fiber utilization, further expanding the operating band of wavelength division multiplexing (WDM) technology, which traditionally operates in the C-band, can significantly increase system capacity.

[0003] In order to effectively expand the operating band, it is necessary to study the corresponding combining and decomposing technology to achieve coverage of the O+E+S+C+L bands. Since the transmission loss of light waves transmitted in optical fibers in the O+E+S+C+L bands is uneven, it is necessary to study asymmetric combining and decomposing technologies and devices. Traditional thin-film combining and decomposing units and jumpers can achieve asymmetric combining and decomposing within a certain band, but this solution requires larger thin-film devices and needs to be used in conjunction with jumpers, resulting in general overall stability and the need for further performance improvement. Moreover, the asymmetric combining and decomposing devices currently reported cannot achieve dynamic adjustment of the output power of each wavelength, which greatly limits the flexibility and reconfigurability of the system.

[0004] In order to obtain an intelligent asymmetric combiner and decoder chip with adjustable output wavelength transmittance, it is necessary to propose new working mechanisms, new materials and new structures to achieve fine adjustment of the characteristics of each wavelength, and thus realize non-uniform output across the entire band. Summary of the Invention

[0005] The purpose of the present invention is to address the shortcomings of the above-mentioned background technology, provide an asymmetric combiner and demultiplexer chip power adjustment unit based on TCO material, introduce transparent conductive oxide material, construct a plasma metal oxide semiconductor (MOS) effect, and achieve full-band non-uniform output of the asymmetric combiner and demultiplexer chip and dynamically adjust the output power of each working wavelength, thereby solving the technical problems of thin-film asymmetric combiner and demultiplexer chips being large in size, poor in stability, and unable to dynamically adjust the output power of each working wavelength.

[0006] The present invention adopts the following technical solutions to achieve the above-mentioned purpose:

[0007] An asymmetric wave combiner chip power regulation unit based on TCO materials includes: a waveguide layer, a transparent conductive oxide material layer, an oxide layer, and a metal layer. The waveguide layer is formed on the upper surface of a lower cladding layer, and the transparent conductive oxide material layer, the oxide layer, and the metal layer are formed between the upper cladding layer and the waveguide layer. The transparent conductive oxide material layer covers the upper surface of the waveguide layer and extends to have a surface for connecting to a second TiN metal electrode. The oxide layer covers the upper surface of the transparent conductive oxide material layer, and the metal layer covers the upper surface of the oxide layer. The transparent conductive oxide material layer and the metal layer are respectively connected to the metal electrode on the upper cladding layer through vias. An external electrical signal acts on the transparent conductive oxide material layer and the metal layer simultaneously to achieve MOS effect regulation, thereby controlling the size of the imaginary part of the refractive index of the transparent conductive oxide material. The optical power within the waveguide array is dynamically controlled through the interaction between the MOS mode and the working mode within the output waveguide array.

[0008] An intelligent asymmetric combiner / demultiplexer chip includes a 180-degree curved input waveguide, a T-type input coupler, a phase-delay array waveguide, a T-type output coupler, an output waveguide array, a power regulation unit, and a closed-loop feedback control system. The 180-degree curved input waveguide is connected to the T-type input coupler, the phase-delay array waveguide is located between the T-type input coupler and the T-type output coupler, the output portion of the T-type output coupler is connected to the output waveguide array, and a power regulation unit is arranged in each channel of the output waveguide array. The proposed asymmetric combiner / demultiplexer chip is constructed based on photonic integration technology and comprises a substrate, a lower cladding, a core layer, and an upper cladding layer stacked from bottom to top. The 180-degree curved input waveguide, T-type input coupler, phase-delay array waveguide, T-type output coupler, and output waveguide array are all formed in the core layer. The 180-degree bent input waveguide inputs a group of optical signals with different wavelengths. The phase delay array waveguide performs phase delay processing on the optical signals of each wavelength. The power adjustment unit on each channel of the output waveguide array adjusts the power of the optical signal of one wavelength respectively. Each channel of the output waveguide array outputs the optical signals of each wavelength after power adjustment in real time.

[0009] The 180-degree curved input waveguide consists of an input straight waveguide, a curved waveguide, and an arc waveguide connected in sequence, which can achieve ultra-low loss propagation of input multi-wavelength optical power and greatly reduce the chip size.

[0010] The T-type input coupler and T-type output coupler are based on the T-type waveguide structure, which can reduce the structure size and realize multi-wavelength splitting and combining.

[0011] The phase delay array waveguide is composed of multiple arc waveguides of different lengths. Each arc waveguide performs phase delay processing on an optical signal of one wavelength and can provide different phase delays for different input wavelengths.

[0012] The closed-loop feedback control system inputs the energy signal of each channel wavelength of the output waveguide array, compares the energy signal of each channel wavelength of the output waveguide array with the calibrated power, and generates an electrical signal loaded on the transparent conductive oxide material layer and the metal layer through the control algorithm, thereby adjusting the optical power output of each channel of the output waveguide array.

[0013] The asymmetric combiner and demultiplexer chip can realize multi-wavelength unequal loss splitting within the full band of O+E+S+C+L, and the wavelength output characteristics are adjustable; the internal working mode of the chip can be either transverse electric mode or transverse magnetic mode; the mode order can be either fundamental mode or high-order mode.

[0014] As a further improvement of the present invention, the asymmetric wave combiner and decoder chip can be based on any material platform of silicon on insulator, silicon dioxide on silicon, InP, GaAs, polymer, lithium niobate, diamond, and chalcogenide material platforms.

[0015] As a further improvement of the present invention, the transparent conductive oxide material may be based on any one of indium tin oxide, graphene, gallium zinc oxide, and vanadium dioxide.

[0016] The present invention adopts the above technical solution and has the following beneficial effects:

[0017] (1) The power regulation unit of the present invention only requires tens or even dozens of fJ / bit of power consumption by introducing the MOS effect based on transparent conductive oxide materials, and can achieve GHz or even THz power regulation rate. The power regulation unit is used to adjust the transmittance of the asymmetric combiner and demultiplexer chip, so that the asymmetric combiner and demultiplexer chip can cover the full band of O+E+S+C+L in the optical communication system, realize full-band energy non-balanced wavelength division and dynamic power adjustment. In addition, the power regulation unit is universal for existing photonic integrated asymmetric combiner and demultiplexer chips. The asymmetric combiner and demultiplexer chip using the power regulation unit has strong scalability and can realize arbitrary selection of two wavelengths to multiple wavelengths, greatly improving the number of channels in the WDM system and the fiber utilization rate.

[0018] (2) The present invention combines a closed-loop control system to achieve arbitrary adjustment of the optical power in the entire band, providing core components for a reconfigurable intelligent optical network. The proposed adjustment method has low power consumption, high response time and fast adjustment.

[0019] (3) The power adjustment unit of the present invention, in conjunction with the T-type input coupler and the T-type output coupler, can greatly improve the adjustment accuracy of the transmittance of each wavelength, with smaller errors.

[0020] (4) The power regulation unit of the present invention can be integrated with the asymmetric wave combining and decomposing chip. Therefore, based on the photonic integration technology, an asymmetric wave combining and decomposing chip with high integration, excellent and stable performance and mature technology can be provided.

[0021] In summary, the present invention realizes a high-performance asymmetric wave combining and decomposition chip by introducing a new mechanism (MOS effect), a new material (transparent conductive oxide material), and a new structure (multi-layer MOS structure). BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural diagram of the intelligent asymmetric wave combining and decomposing chip of the present invention.

[0023] Figure 2 It is a schematic diagram of the three-dimensional structure of the power regulation unit in the present invention.

[0024] Figure 3 It is a schematic diagram of the two-dimensional cross-sectional structure of the power regulation unit in the present invention.

[0025] Figure 4 It is a block diagram of the closed-loop feedback control system in the present invention.

[0026] Figure 5 This is the output spectrum of the intelligent asymmetric wave combining and decomposing chip of the present invention.

[0027] Explanation of the numbers in the figure: 001, 180-degree bent input waveguide, 002, T-type input coupler, 003, phase delay array waveguide, 004, T-type output coupler, 005, output waveguide array, 006, power adjustment unit array, 007, lower cladding, 008, upper cladding, 601, transparent conductive oxide material layer, 602, oxide layer, 603, metal layer, 604, waveguide layer, 901, first TiN metal electrode, 902, first via, 903, second TiN metal electrode, 904, second via. DETAILED DESCRIPTION

[0028] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] like Figure 1 、 Figure 2 ,as well as Figure 3 The present invention provides an intelligent asymmetric wave combiner and decoder chip based on transparent conductive oxide materials, which can realize dynamic adjustment of non-uniform output of multiple wavelengths in the O+E+S+C+L band.

[0030] like Figure 1As shown, the intelligent asymmetric wave combining and decomposing chip includes: a 180-degree curved input waveguide 001, a T-type input coupler 002, a phase delay array waveguide 003, a T-type output coupler 004, an output waveguide array 005, a power adjustment unit array 006 and a closed-loop feedback control system (such as Figure 4 ); a 180-degree bent input waveguide 001 is connected to a T-type input coupler 002; a phase delay array waveguide 003 is located between the T-type input coupler 002 and the T-type output coupler 004; the output portion of the T-type output coupler 004 is connected to an output waveguide array 005; a power adjustment unit is arranged on each channel of the output waveguide array 005; and the power adjustment units arranged on each channel of the output waveguide array 005 constitute a power adjustment unit array 006.

[0031] like Figure 1 As shown, the present invention uses a 180-degree curved input waveguide 001 to input λ1 to λ N There are N wavelengths of optical signals in total, and each channel of the output waveguide array 005 outputs λ1 to λ N Based on the power adjustment unit array 006, the wavelength of the optical signal can be adjusted from λ1 to λ N The output power of each wavelength is dynamically adjustable. In this embodiment, taking λ1 to λ8 as an example, they correspond to λ1 = 1431 nm, λ2 = 1451 nm, λ3 = 1471 nm, λ4 = 1491 nm, λ5 = 1511 nm, λ6 = 1531 nm, λ7 = 1551 nm, and λ8 = 1571 nm, respectively. λ1 and λ2 are in the E-band, λ3 to λ5 are in the S-band, λ6 and λ7 are in the C-band, and λ8 is in the L-band.

[0032] like Figure 2 、 Figure 3As shown, each power regulation unit includes: a waveguide layer 604, a transparent conductive oxide material layer 601, an oxide layer 602 and a metal layer 603. The waveguide layer 604 is made of silicon material and is conformally formed on the core layer with the waveguide layer of the asymmetric wave combiner chip. The waveguide layer 604 is formed on the upper surface of the lower cladding layer 007. The transparent conductive oxide material layer 601, the oxide layer 602 and the metal layer 603 are formed between the upper cladding layer 008 and the core layer. The transparent conductive oxide material layer 601 covers the upper surface of the waveguide layer 604 and extends to have a surface for connecting to the second TiN metal electrode 903. The oxide layer 602 covers the upper surface of the transparent conductive oxide material layer 601. The metal layer 603 covers the upper surface of the oxide layer 602. The material layer 601 is connected to the second TiN metal electrode 903 on the upper cladding layer through the second via 904, and the metal layer 603 is connected to the first TiN metal electrode 901 on the upper cladding layer through the first via 902. The lower cladding layer 007 and the upper cladding layer 008 are made of silicon dioxide material, the waveguide layer 604 is made of silicon material, the transparent conductive oxide material layer 601 is made of ITO material, the oxide layer 602 is made of HfO2 material, and the metal layer 603 is made of copper material. An external electrical signal is applied to the transparent conductive oxide material layer 601 and the metal layer 603 through the TiN metal electrode, and the voltage is dynamically adjusted from 0V to 2.4V. The refractive index of the transparent conductive oxide ITO material is dynamically adjustable between 1.960 + 0.003i and 0.479 + 0.646i.

[0033] like Figure 4 As shown, an external closed-loop feedback control system receives the output power of each wavelength of the output waveguide array, and then compares it with the calibrated power, thereby outputting a control signal to the transparent conductive oxide material layer and the metal layer, realizing dynamic regulation of the power of each wavelength and intelligent spontaneous start and end.

[0034] Depend on Figure 5 From the output spectrum characteristics of the intelligent asymmetric combiner and demultiplexer chip shown in the figure, it can be seen that the output losses of the optical signals of the four wavelengths λ1 to λ4 are 0.5dB, 0.9dB, 1.3dB, and 1.8dB, respectively, and the output losses of the optical signals of the wavelengths λ5 to λ8 are all 2dB, verifying that the intelligent asymmetric combiner and demultiplexer chip implemented by the power adjustment unit proposed in the present invention can achieve power adjustment for each wavelength.

[0035] In summary, the present invention provides an intelligent asymmetric combiner / demultiplexer chip based on transparent conductive oxide materials. This chip can cover the full wavelength bands of optical communication systems (O+E+S+C+L), achieving full-band energy asymmetric wavelength division and dynamic power adjustment. By incorporating the MOS effect of transparent conductive oxide materials, it achieves ultra-low power consumption and ultra-high power regulation. Based on photonic integration technology, the proposed asymmetric combiner / demultiplexer chip boasts high integration, excellent and stable performance, and mature manufacturing processes. Combined with a closed-loop control system, the proposed chip enables full-band optical power adjustment, providing a core component for reconfigurable intelligent optical networks. The proposed intelligent asymmetric combiner / demultiplexer chip can be fabricated using other materials (including but not limited to silicon dioxide on silicon, InP, GaAs, polymers, lithium niobate, diamond, and chalcogenides). While this invention demonstrates eight-wavelength demultiplexing capabilities, this structure can also achieve multiplexing. While the chip structure presented in this invention only covers eight wavelengths, it can be expanded beyond eight wavelengths to achieve a wider range of asymmetric combiner / demultiplexer effects.

[0036] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. Asymmetric wave combiner and demultiplexer chip power regulation unit based on TCO material, characterized by: include: a waveguide layer formed on the upper surface of the lower cladding layer; a transparent conductive oxide material layer, covering the upper surface of the waveguide layer and extending to have a surface for connecting to the second metal electrode, and connected to the second metal electrode on the upper cladding layer through a second via hole; an oxide layer covering an upper surface of the transparent conductive oxide material layer; and, The metal layer covers the upper surface of the oxide layer and is connected to the first metal electrode on the upper cladding layer through a first via hole. The first metal electrode and the second metal electrode are loaded with a voltage signal. The MOS effect generated by the voltage signal acting on the transparent conductive oxide material layer and the metal layer simultaneously controls the size of the imaginary part of the refractive index of the transparent conductive oxide material, thereby adjusting the wavelength energy of each channel of the output waveguide array of the asymmetric wave combiner chip.

2. The asymmetric combiner / decomposer chip power regulation unit based on TCO material according to claim 1 is characterized in that: The waveguide layer is formed on the core layer, and the transparent conductive oxide material layer, the oxide layer and the metal layer are formed between the upper cladding layer and the core layer.

3. The asymmetric combiner / decomposer chip power regulation unit based on TCO material according to claim 1, characterized in that: The waveguide layer is prepared based on silicon material, the transparent conductive oxide material layer is prepared based on ITO material, the oxide layer is prepared based on HfO2 material, and the metal layer is prepared based on copper material.

4. The asymmetric combiner / decomposer chip power regulation unit based on TCO material according to claim 1, characterized in that: The transparent conductive oxide material layer is prepared based on indium tin oxide, graphene, gallium zinc oxide, or vanadium dioxide.

5. An intelligent asymmetric wave combining and decoding chip, characterized in that: include: The input waveguide is bent 180 degrees to transmit a group of optical signals with different wavelengths, which cover the full wavelength bands of O+E+S+C+L. The input coupler is a T-shaped waveguide structure, and its input part is connected to the 180-degree bent input waveguide. A phase delay array waveguide comprises a plurality of arc waveguides having the same number of wavelengths as the wavelengths of the optical signal transmitted by the 180-degree bent input waveguide. The lengths of the arc waveguides are different, and the input ends of the arc waveguides are connected to the output of the input coupler. The optical signals of each wavelength are phase-delayed before being output. The output coupler is a T-shaped waveguide structure, the input portion of which is connected to the output end of the phase delay array waveguide, and transmits the optical signals of each wavelength after phase delay processing to the output waveguide array; an output waveguide array comprising output waveguides having the same number of wavelengths as the group of optical signals transmitted by the 180-degree bent input waveguides, the input end of each output waveguide being connected to the output portion of the output coupler, and each channel formed by each output waveguide being connected to a power adjustment unit according to claim 1; and, The closed-loop feedback control system collects the wavelength energy signal of each channel of the output waveguide array, compares the wavelength energy signal of each channel of the output waveguide array with the calibrated power, and generates a voltage signal loaded on the first metal electrode and the second metal electrode of each power adjustment unit with the goal of making the power of the wavelength energy signal of each channel of the output waveguide array approach the calibrated power.

6. The intelligent asymmetric wave combining and decoding chip according to claim 5, characterized in that: The 180-degree curved input waveguide includes an input straight waveguide, a curved waveguide and an arc waveguide connected in sequence.

7. The intelligent asymmetric wave combining and decoding chip according to claim 5, characterized in that: The 180-degree bent input waveguide, input coupler, phase delay array waveguide, output coupler, and output waveguide array are all formed in the core layer.

8. The intelligent asymmetric wave combining and decoding chip according to claim 5, characterized in that: The intelligent asymmetric wave combining and decoding chip is prepared based on any one of the material platforms of silicon on insulator, silicon dioxide on silicon, InP, GaAs, polymer, lithium niobate, diamond, and chalcogenide material platforms.

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