An all-optical triode light modulation system, modulation method and application thereof

Abstract

This invention provides an all-optical transistor optical modulation system, its modulation method, and its applications. The all-optical transistor optical modulation system includes a pump source, a signal source, and a micro-ring modulator. The micro-ring modulator includes a micro-ring resonator and a van der Waals material. Pump light output from the pump source is incident on the van der Waals material from one side, generating resonant light absorption. Signal light output from the signal source is coupled into the micro-ring resonator and interacts with the van der Waals material, thereby modulating the signal light with the pump light. This invention utilizes the limited bandgap and resonant light absorption in the visible and near-infrared bands of van der Waals semiconductor materials, as well as the resonant characteristics of a silicon-based micro-ring resonator, to fabricate an all-optical modulation system with a simple structure, high modulation rate, and short response time. This enables rapid modulation of communication optical signals and allows for all-optical modulation of optical phase and / or amplitude.

Description

Technical Field

[0001] This invention belongs to the field of information and communication technology, specifically relating to an all-optical triode optical modulation system, its modulation method, and its application. Background Technology

[0002] Optical modulators play a crucial role in fiber optic systems by modulating carrier optical signals. They are a key factor in achieving high-speed transmission and processing of optical signals, a critical component of modern telecommunications networks and microwave photonics systems, and a cornerstone of emerging fields such as quantum photonics. As existing and emerging technologies place increasingly higher demands on compact, efficient, fast, and broadband optical processing, the need for electro-optic modulators with higher performance and smaller size is becoming increasingly urgent. Therefore, it is essential to find optical material systems that offer stronger light confinement, better modulation effects, and easier integration.

[0003] However, existing optical modulation technologies still face a series of pressing challenges. Specifically, traditional optical modulation depth is limited, making it difficult to achieve the required high-efficiency signal conversion; energy consumption is high, increasing system operating costs and limiting its feasibility in large-scale deployment; material selection is limited, with existing materials having shortcomings in nonlinear effects and optical absorption, restricting the improvement of modulation performance; technological maturity is insufficient, with some key technologies not yet meeting commercialization standards, affecting their promotion in practical applications; and system integration is difficult, with compatibility and interoperability with existing optical communication systems requiring further optimization.

[0004] All-optical transistors (APTs) use light waves instead of electron flow, employing photons as the medium to perform signal scaling and modulation. This concept deeply integrates nonlinear optics, laser engineering, and advanced materials science, aiming to develop a new generation of optical control devices capable of effectively controlling the intensity and phase of optical signals, playing a crucial role in optical communication, optical computing, and even future quantum information processing. However, while traditional optical transistors have a certain application foundation in optoelectronics, their inherent defects cannot be ignored. The main problem is that traditional transistors generally use semiconductor materials such as silicon and germanium. The band structure of these materials limits their effective application in specific optical bands (such as ultraviolet and infrared), and their physical and chemical properties make the devices susceptible to performance degradation in harsh environments such as high temperature and high humidity. In addition, the limited carrier mobility and recombination rate of semiconductor materials result in limited modulation efficiency and bandwidth, making it difficult to meet the needs of modern high-speed, broadband optical communication systems. At the same time, the manufacturing process of traditional optical transistors is complex, integration is difficult, and costs are high. Furthermore, their performance is prone to degradation after long-term operation, and their stability and reliability are insufficient.

[0005] In contrast, optical transistors based on van der Waals materials exhibit significant advantages. Van der Waals materials possess unique band structures and excellent light absorption characteristics, enabling efficient photoelectric conversion across a wider optical wavelength range. Furthermore, these materials typically possess excellent chemical and thermal stability, maintaining stable performance even in harsh environments. More importantly, the excitons and polaritons in van der Waals materials exhibit rapid and efficient excitation and relaxation processes, allowing optical transistors based on these materials to achieve high-speed, efficient optical modulation with a wider modulation bandwidth, meeting the demands of modern high-speed, broadband optical communication systems. This makes van der Waals-based optical transistors have broader application prospects and higher performance in modern optoelectronics. Summary of the Invention

[0006] Therefore, the purpose of this invention is to overcome the defects in the prior art and provide an all-optical triode optical modulation system, its modulation method and application.

[0007] To address the shortcomings of slow modulation speed in electro-optic modulators and the immature fabrication technology and lack of stability of existing all-optical modulators, this invention proposes an all-optical triode optical modulation system based on van der Waals semiconductor materials. This invention utilizes the limited bandgap and resonant light absorption in the visible and near-infrared bands of van der Waals semiconductor materials, as well as the resonant characteristics of silicon-based microring resonators, to fabricate an all-optical modulation system with a simple structure, high modulation rate, and short response time, enabling rapid modulation of communication optical signals.

[0008] Before describing the content of this invention, the following terms are defined as follows:

[0009] The term "TMDs" refers to transition metal dichalcogenides.

[0010] The term "single-mode fiber" refers to an optical fiber that has only one transmission mode, and its core diameter is usually small, for example, including but not limited to core diameters of only 9 or 10 μm.

[0011] To achieve the above objectives, a first aspect of the present invention provides an all-optical transistor optical modulation system, the all-optical transistor optical modulation system comprising: a pump light source, a signal light source, and a micro-ring modulator, wherein the micro-ring modulator comprises a micro-ring resonator and a van der Waals material; wherein,

[0012] The pump light output from the pump light source is incident on the van der Waals material from one side, generating resonant light absorption. The signal light output from the signal light source is coupled into the micro-ring resonator and interacts with the van der Waals material, so that the pump light modulates the signal light.

[0013] According to the all-optical transistor optical modulation system of the first aspect of the present invention, the micro-ring resonator comprises a straight waveguide and a micro-ring waveguide; wherein,

[0014] The materials of the straight waveguide and the micro-ring waveguide are selected from one or more of the following: silicon, silicon nitride, silicon dioxide, preferably silicon or silicon nitride, and most preferably silicon.

[0015] According to the all-optical transistor optical modulation system of the first aspect of the present invention, wherein,

[0016] The radius of the microring waveguide is 0.2–0.6 μm, preferably 0.3–0.5 μm, and more preferably 0.35–0.45 μm; and / or

[0017] The gap width between the straight waveguide and the micro-ring waveguide is 50–150 nm, preferably 80–120 nm, and more preferably 90–100 nm.

[0018] According to the all-optical triode optical modulation system of the first aspect of the present invention, the micro-ring modulator further includes a grating coupler and / or a signal generator; wherein,

[0019] The signal light is coupled to the straight waveguide through the grating coupler, and then coupled to the micro-ring resonator; and / or

[0020] The signal generator is used to modulate the pump light and incident it onto the van der Waals material through a single-mode optical fiber.

[0021] According to the all-optical transistor optical modulation system of the first aspect of the present invention, wherein,

[0022] The van der Waals material is coated on the microring waveguide of the microring resonator; and / or

[0023] The band gap of the van der Waals material is 0 eV to 2.5 eV, preferably 1.0 eV to 2.3 eV, and more preferably 1.5 eV to 2.1 eV.

[0024] According to the all-optical transistor optical modulation system of the first aspect of the present invention, the van der Waals material is selected from one or more of the following: graphene, TMDs, black phosphorus, preferably graphene or TMDs, and most preferably TMDs; wherein,

[0025] The chemical formula of the TMDs is MX2, wherein,

[0026] M is a transition metal element, preferably selected from one or more of the following: Ti, V, Ta, Mo, W, Re, more preferably selected from one or more of the following: Ti, Mo, W, Re, and even more preferably Mo or W;

[0027] X is selected from one or more of the following: S, Se, Te, more preferably S or Se, and most preferably S;

[0028] Preferably, the TMDs are selected from one or more of the following: molybdenum disulfide, molybdenum diselenide, tungsten disulfide, tungsten diselenide, molybdenum distelluride, tungsten distelluride, and more preferably from one or more of the following: molybdenum disulfide, molybdenum diselenide, tungsten disulfide, tungsten diselenide.

[0029] According to the all-optical transistor optical modulation system of the first aspect of the present invention, wherein,

[0030] The pump light has a wavelength of 400–700 nm, preferably 450–650 nm, and more preferably 500–600 nm; and / or

[0031] The wavelength of the signal light is 1500-1600nm, preferably 1520-1570nm, and more preferably 1530-1550nm.

[0032] A second aspect of the present invention provides a method for modulating light, the method comprising modulating light using the all-optical triode optical modulation system described in the first aspect;

[0033] Preferably, the modulation of the light includes: all-optical modulation of the optical phase and / or all-optical modulation of the optical amplitude.

[0034] A second aspect of the present invention provides a method for modulating light, the method comprising modulating light using the all-optical triode optical modulation system described in the first aspect, the modulation method comprising:

[0035] The pump light output from the pump source is modulated by the signal generator and then incident through a single-mode fiber onto the van der Waals material covering the micro-ring waveguide. Resonant light absorption alters the refractive index of the van der Waals material. The signal light is coupled to the straight waveguide via the grating coupler and then to the micro-ring resonator, where it interacts with the van der Waals material. This allows the pump light to modulate the signal light, outputting a waveform consistent with the pump light, thus achieving all-optical modulation of the optical phase and / or amplitude.

[0036] The third aspect of the invention provides the application of the all-optical transistor optical modulation system described in the first aspect in the fabrication of an apparatus for realizing all-optical modulation of optical phase and / or all-optical modulation of optical amplitude.

[0037] According to a preferred embodiment of the present invention, the all-optical transistor optical modulation system of the present invention operates as follows:

[0038] The testing process of the all-optical transistor optical modulation system is as follows: Figure 1As shown, a tapered optical fiber is used to incident a pump light source onto a silicon-based microring covered with van der Waals material. The energy of the pump light far exceeds the energy level of the tungsten disulfide bandgap, thus it acts as an absorber for the pump light. A grating coupler couples the continuous input signal light in the near-infrared communication band into a silicon-based straight waveguide, and then into a microring resonator. The strong interaction between the optical field within the waveguide and the van der Waals material as the signal light passes through enables the pump light to effectively modulate the signal light, thereby outputting a waveform consistent with the pump light.

[0039] The working principle of the all-optical transistor optical modulation of this invention is as follows:

[0040] All-optical modulation utilizes a pump beam to modulate the input signal light (continuous light). Under laser pulse excitation, the carrier density and distribution of a two-dimensional material undergo significant changes, resulting in variations in the real and imaginary parts of its complex refractive index. Based on an all-optical triode-based optical modulation system using van der Waals semiconductor materials, the modulated pump light is incident from one side onto a micro-ring of van der Waals material. The resonant absorption of the van der Waals material causes a change in its refractive index. This change in the refractive index of the van der Waals material at the micro-ring further affects the effective real or imaginary part of the refractive index of the input signal light into the underlying silicon waveguide, leading to changes in the phase or intensity of the signal light, thus achieving optical phase or amplitude modulation.

[0041] Compared with the prior art, the all-optical transistor optical modulation system, its modulation method, and its application of the present invention can have, but are not limited to, the following beneficial effects:

[0042] This invention utilizes the limited bandgap and resonant light absorption in the visible and near-infrared bands of van der Waals semiconductor materials, as well as the resonant characteristics of silicon-based microring resonators, to fabricate an all-optical modulation system with a simple structure, fast modulation rate, and short response time. This system enables rapid modulation of communication optical signals and can achieve all-optical modulation of optical phase and / or optical amplitude. Attached Figure Description

[0043] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings, wherein:

[0044] Figure 1 A schematic diagram of the operation of the all-optical triode optical modulation system of the present invention is shown.

[0045] Figure 2 The waveforms of the pump light and the output signal light are shown as sinusoidal waves.

[0046] Figure 3 The waveforms of the pump light and the output signal light are shown as square waves.

[0047] Figure 4 The waveforms of the pump light and the output signal light are shown as triangular waves.

[0048] Figure 5 A structural diagram of the all-optical triode optical modulation system of the present invention is shown. Detailed Implementation

[0049] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. However, it should be understood that these embodiments are merely for more detailed and specific explanation and should not be construed as limiting the present invention in any way.

[0050] This section provides a general description of the materials and testing methods used in the experiments of this invention. While many of the materials and methods of operation used to achieve the objectives of this invention are well known in the art, the invention is still described in as much detail as possible herein. It will be apparent to those skilled in the art that, unless otherwise stated in the context, the materials and methods of operation used in this invention are well known in the art.

[0051] Example 1

[0052] This embodiment is an exemplary description of the all-optical transistor optical modulation system and modulation method of the present invention.

[0053] The all-optical triode optical modulation system of the present invention includes: a pump source, a signal source, and a micro-ring modulator. The micro-ring modulator includes a micro-ring resonator and a van der Waals material. The micro-ring resonator includes a straight waveguide and a micro-ring waveguide, and the van der Waals material covers the micro-ring waveguide of the micro-ring resonator. Figure 5 As shown.

[0054] The microring modulator also includes a grating coupler and a signal generator. The signal light is coupled to the straight waveguide through the grating coupler and then to the microring resonator. The signal generator is used to modulate the pump light.

[0055] In this embodiment, tungsten disulfide is used as the van der Waals material, with a bandgap of 2.1 eV. Silicon is used as the material for both the straight waveguide and the micro-ring waveguide. The radius of the micro-ring waveguide is 10 μm, the gap width between the straight waveguide and the micro-ring waveguide is 90 nm, the wavelength of the pump light is 520 nm, and the wavelength of the signal light is 1539 nm.

[0056] The working method of the all-optical transistor optical modulation system of the present invention is as follows:

[0057] The testing process of the all-optical transistor optical modulation system is as follows: Figure 1As shown, a tapered optical fiber is used to illuminate the pump light onto a section of the microring waveguide covered with van der Waals material. The energy of the pump light far exceeds the bandgap of tungsten disulfide, thus it acts as an absorber for the pump light. A grating coupler couples the continuous input signal light in the near-infrared communication band into the silicon-based straight waveguide, and then into the microring resonator. The strong interaction between the evanescent field within the waveguide and the van der Waals material as the signal light passes through enables effective modulation of the signal light by the pump light, resulting in an output waveform consistent with the pump light, thus achieving optical phase modulation and / or optical amplitude modulation.

[0058] Examples 2-3

[0059] This embodiment is another exemplary description of the all-optical triode optical modulation system of the present invention.

[0060] The all-optical triode optical modulation systems in Examples 2 and 3 are the same as those in Example 1, except for the conditions listed in Table 1.

[0061] Table 1. All-optical triode optical modulation systems of Examples 2-3

[0062]

[0063] Example 4

[0064] This embodiment presents the performance test results of the all-optical triode optical modulation system of the present invention.

[0065] This embodiment uses the all-optical triode optical modulation system of Examples 1-3 to perform the following tests.

[0066] In this measurement, the wavelengths of the pump light source and signal light used are shown in Table 1 and Example 1, respectively. The pump light signal was modulated using a signal generator and then irradiated onto a micro-ring waveguide covered with van der Waals material via a single-mode tapered fiber. Continuous signal light was coupled into the straight waveguide by a grating. The optical signal received from the output port of the straight waveguide was the modulated signal. Finally, the output signal light was coupled into a near-infrared photodetector, which converted the optical signal into an electrical signal for display on an oscilloscope.

[0067] The pump light source was controlled by a signal generator, and the input signal light was modulated under sinusoidal, square, and triangular wave input conditions, respectively. The results are as follows. Figures 2-4As shown. The pump light frequency is 1 kHz, and the optical power is 0.5 mW. The input signal light is continuous light with an optical power of 10 mW. Under the excitation of the modulated pump light, the frequency and waveform of the output signal light of the all-optical triode optical modulation system in Examples 1-3 are the same as those of the pump light, indicating that all-optical modulation of the signal light has been achieved. When the pump light is a sine wave and a triangular wave, the input power of the pump light of the all-optical triode optical modulation system in Examples 1-3 changes continuously in the range of 0-0.5 mW. At this time, the intensity of the output light signal increases linearly with the increase of the input power of the excitation light. This is because the light absorption of the van der Waals material is proportional to the pump light power before reaching saturation absorption. The change in optical power mainly affects the absorption of the material, thereby affecting the imaginary part of the refractive index, thus achieving modulation of the signal light amplitude. When the pump light is a square wave (switching) waveform input, it mainly affects the phase of the output signal light, thus achieving phase modulation of the signal light.

[0068] While the effects of some embodiments have been shown above, those skilled in the art should understand that, based on the concept of the invention, other embodiments not specifically shown or other technical solutions of the invention not shown in the embodiments can also achieve the same technical effects as those claimed in the summary section:

[0069] This invention utilizes the limited bandgap and resonant light absorption in the visible and near-infrared bands of van der Waals semiconductor materials, as well as the resonant characteristics of silicon-based microring resonators, to fabricate an all-optical modulation system with a simple structure, fast modulation rate, and short response time. This system enables rapid modulation of communication optical signals and can achieve all-optical modulation of optical phase and / or optical amplitude.

[0070] Although the invention has been described to a certain extent, it is apparent that appropriate variations can be made to the various conditions without departing from the spirit and scope of the invention. It is understood that the invention is not limited to the described embodiments, but falls within the scope of the claims, which include equivalent substitutions for each of the elements.

Claims

1. An all-optical triode light modulation system, characterized by, The all-optical triode light modulation system comprises a pump light source, a signal light source and a micro-ring modulator, the micro-ring modulator comprises a micro-ring resonator and a van der Waals material; wherein, The pump light output by the pump light source is incident on the van der Waals material from one side to generate resonant light absorption, the signal light output by the signal light source is coupled into the micro-ring resonator and interacts with the van der Waals material, so that the pump light modulates the signal light; and The van der Waals material is selected from one or more of the following: TMDs, black phosphorus. The wavelength of the pump light is 400-700 nm, and the wavelength of the signal light is 1500-1600 nm.

2. The all-optical triode light modulation system of claim 1, wherein, The micro-ring resonator comprises a straight waveguide and a micro-ring waveguide; wherein, The material of the straight waveguide and the micro-ring waveguide is selected from one or more of the following: silicon, silicon nitride, silicon dioxide.

3. The all-optical triode light modulation system of claim 2, wherein, The material of the straight waveguide and the micro-ring waveguide is silicon or silicon nitride.

4. The all-optical triode light modulation system of claim 3, wherein, The material of the straight waveguide and the micro-ring waveguide is silicon.

5. The all-optical triode light modulation system of claim 2, wherein: The radius of the micro-ring waveguide is 0.2-0.6 μm; and / or The gap width between the straight waveguide and the micro-ring waveguide is 50-150 nm.

6. The all-optical triode light modulation system of claim 5, wherein: The radius of the micro-ring waveguide is 0.3-0.5 μm; and / or The gap width between the straight waveguide and the micro-ring waveguide is 80-120 nm.

7. The all-optical triode light modulation system of claim 6, wherein: The radius of the micro-ring waveguide is 0.35-0.45 μm; and / or The gap width between the straight waveguide and the micro-ring waveguide is 90-100 nm.

8. The all-optical triode light modulation system according to any one of claims 2 to 7, wherein, The micro-ring modulator further comprises a grating coupler and / or a signal generator; wherein, The signal light is coupled into the straight waveguide through the grating coupler and then into the micro-ring resonator; and / or The signal generator is used to modulate the pump light and is incident on the van der Waals material through a single-mode optical fiber.

9. The all-optical triode light modulation system according to any one of claims 2 to 7, wherein, The van der Waals material is covered on the micro-ring waveguide of the micro-ring resonator.

10. The all-optical triode light modulation system according to any one of claims 2 to 7, wherein, The band gap of the van der Waals material is 0 eV-2.5 eV.

11. The all-optical triode light modulation system of claim 10, wherein, The band gap of the van der Waals material is 1.0 eV-2.3 eV.

12. The all-optical triode light modulation system of claim 11, wherein, The band gap of the van der Waals material is 1.5 eV-2.1 eV.

13. The all-optical triode light modulation system according to any one of claims 1 to 7, wherein, The van der Waals material is TMDs, and the chemical formula of the TMDs is MX2, wherein, M is one or more transition metal elements selected from the following: Ti, V, Ta, Mo, W, Re, X is selected from one or more of the following: S, Se, Te.

14. The all-optical triode light modulation system of claim 13, wherein, The chemical formula of the TMDs is MX2, wherein, M is one or more transition metal elements selected from the following: Ti, Mo, W, Re; X is S or Se.

15. The all-optical triode light modulation system of claim 14, wherein, The chemical formula of the TMDs is MX2, wherein, M is Mo or W; X is S.

16. The all-optical triode light modulation system according to any one of claims 1 to 7, wherein, The van der Waals material is a TMD, the TMD has a chemical formula of MX2, and the TMD is selected from one or more of the following: molybdenum disulfide, molybdenum diselenide, tungsten disulfide, tungsten diselenide, molybdenum ditelluride, and tungsten ditelluride.

17. The all-optical triode light modulation system of claim 16, wherein, The TMD is selected from one or more of the following: molybdenum disulfide, molybdenum diselenide, tungsten disulfide, and tungsten diselenide.

18. The all-optical triode optical modulation system according to any one of claims 1 to 7, wherein: the wavelength of the pump light is 450-650 nm; and / or the wavelength of the signal light is 1520-1570 nm.

19. The all-optical triode optical modulation system according to claim 17, wherein: the wavelength of the pump light is 500-600 nm; and / or the wavelength of the signal light is 1530-1550 nm.

20. A method of modulating light, comprising: The modulation method comprises modulating light using the all-optical triode optical modulation system according to any one of claims 1 to 19.

21. The modulation method of claim 20, wherein, The modulation of the light comprises all-optical modulation of optical phase and / or all-optical modulation of optical amplitude.

22. A method of modulating light, comprising: The modulation method comprises modulating light using the all-optical triode optical modulation system according to claim 8, and the modulation method comprises: the pump light output by the pump light source is incident on the micro-ring waveguide covered with the van der Waals material through a single-mode optical fiber after being modulated by the signal generator, and the refractive index of the van der Waals material is changed through resonant light absorption; the signal light is coupled into the straight waveguide through the grating coupler, and then coupled into the micro-ring resonator, interacts with the van der Waals material, so that the pump light modulates the signal light, and a waveform consistent with the pump light is output to realize all-optical modulation of optical phase and / or all-optical modulation of amplitude.

23. Use of the all-optical triode optical modulation system according to any one of claims 1 to 19 in the preparation of a device for realizing the function of all-optical modulation of optical phase and / or all-optical modulation of optical amplitude.

Images