An electro-optic modulator and related devices

Abstract

This application discloses an electro-optic modulator and related devices for achieving good impedance matching, thereby suppressing crosstalk between the positive and negative electrodes and improving the efficiency and bandwidth of electro-optic modulation. The electro-optic modulator provided in this application includes: a transmission line comprising a positive electrode and a negative electrode; one end of the positive electrode is connected to a signal input terminal, and the other end is connected to a target resistor through a first matching resistor; one end of the negative electrode is connected to the signal input terminal, and the other end is connected to the target resistor through a second matching resistor; the first and second matching resistors are used to match the odd-mode characteristic impedance of the transmission line. An optical waveguide includes a first branch and a second branch, with PN junctions on the first and second branches coupled to the positive and negative electrodes, respectively; the two ends of the first branch and the two ends of the second branch are interconnected. A target resistor is used to match the even-mode characteristic impedance of the transmission line and to suppress reverse electrical signals from the first and second matching resistors to the signal input terminal.

Description

Technical Field

[0001] This application relates to the field of signal processing, and more particularly to an electro-optic modulator and related devices. Background Technology

[0002] In the field of optical transmission, electro-optic modulators are used to convert electrical signals into optical signals. A common structure for electro-optic modulators is the differential-driven structure. In this structure, an electrical signal is applied through two electrodes, one positive and one negative. PN junctions are located on the optical waveguides near these electrodes. These PN junctions perform electro-optic conversion on each electrical signal, resulting in two coherent optical signals. Processing these two coherent optical signals yields the final optical signal, thus achieving the conversion from electrical to optical signals.

[0003] However, in differential drive structures, if the distance between the positive and negative electrodes is too close, crosstalk may occur in the electrical signals between the two electrodes. When the PN junction on the optical waveguide performs electro-optic conversion on the crosstalk electrical signal, it generates a crosstalk optical signal, which leads to a decrease in the efficiency and bandwidth of electro-optic modulation. Summary of the Invention

[0004] This application provides an electro-optic modulator and related devices for suppressing crosstalk between positive and negative electrodes, achieving good impedance matching, and thereby improving the efficiency and bandwidth of electro-optic modulation.

[0005] In a first aspect, embodiments of this application provide an electro-optic modulator. The electro-optic modulator includes a transmission line, an optical waveguide, and a target resistor. The transmission line includes a positive electrode and a negative electrode. One end of the positive electrode is connected to a signal input terminal, and the other end is connected to the target resistor via a first matching resistor. One end of the negative electrode is connected to the signal input terminal, and the other end is connected to the target resistor via a second matching resistor. The first and second matching resistors are used to match the odd-mode characteristic impedance of the transmission line. The optical waveguide includes a first branch and a second branch. PN junctions on the first and second branches are coupled to the positive and negative electrodes, respectively. The two ends of the first branch and the two ends of the second branch are interconnected. The target resistor is used to match the even-mode characteristic impedance of the transmission line and to suppress reverse electrical signals from the first and second matching resistors to the signal input terminal.

[0006] In this embodiment, the target resistor can match the even-mode characteristic impedance of the transmission line, thereby reducing the common-mode noise of the transmission line and decreasing the crosstalk of the differential electrical signal. This reduces the noise of the differential electrical signal in the input optical waveguide, thereby reducing the noise of the optical signal obtained by electro-optic modulation and improving the signal-to-noise ratio and electro-optic modulation bandwidth of the electro-optic modulator.

[0007] In one alternative implementation, the first matching resistor and the second matching resistor are grounded via a wire. The target resistor includes the parasitic resistance of this wire. Compared to setting a physical target resistor in the modulator, using the parasitic resistance of the grounding wire as the target resistor simplifies the modulator's structure and makes it easier to implement.

[0008] In one alternative implementation, the modulator further includes a target capacitor. The target capacitor is connected to a first matching resistor and a second matching resistor, and / or, the target capacitor is connected to a target resistor. The target capacitor is used to match the imaginary part of the even-mode characteristic impedance of the transmission line and to suppress leakage of DC signals in the transmission line.

[0009] In this embodiment, the imaginary part of the even-mode characteristic impedance of the transmission line is matched using a target capacitor, resulting in a more complete matching of the even-mode impedance. This better suppresses reverse electrical signals in the transmission line, reduces the power consumption of the electro-optic modulator, and improves the conversion efficiency of the electro-optic modulation. Furthermore, suppressing DC signal leakage in the transmission line using the target capacitor reduces the power consumption of the electro-optic modulator 3000 and increases the signal strength in the transmission line, thereby increasing the intensity of the optical signal in the optical waveguide and ultimately improving the electro-optic modulation conversion efficiency.

[0010] In one alternative implementation, the target capacitor includes the parasitic capacitance of the target resistor. Using the parasitic capacitance of the target resistor as the target capacitor simplifies the modulator's structure compared to adding a physical target capacitor to the modulator.

[0011] In one alternative implementation, the target resistor includes the parasitic resistance of the target capacitor. Using the parasitic resistance of the target capacitor as the target resistor simplifies the modulator's structure compared to setting a physical target resistor within the modulator.

[0012] In an alternative implementation, the modulator further includes a target inductor. The target inductor is connected to a first matching resistor and a second matching resistor, and / or, the target inductor is connected to a target resistor. The target inductor is used to match the imaginary part of the even-mode characteristic impedance of the transmission line and to suppress leakage of AC signals in the transmission line.

[0013] In this embodiment, by using the target inductor to suppress the leakage of AC signals in the transmission line, the amplitude of the high-frequency electrical signals on the transmission line can be increased, thereby increasing the amplitude of the high-frequency optical signals generated on the optical waveguide and achieving an increase in bandwidth.

[0014] In one alternative implementation, the target inductor includes the parasitic inductance of the target resistor. Using the parasitic inductance of the target resistor as the target resistor simplifies the modulator's structure compared to setting a physical target inductor in the modulator.

[0015] In one alternative implementation, the target resistor includes the parasitic resistance of the target inductor. Using the parasitic resistance of the target inductor as the target resistor simplifies the modulator's structure compared to setting a physical target resistor within the modulator.

[0016] In one alternative implementation, the target inductor includes the parasitic inductance of the target capacitor. Using the parasitic inductance of the target capacitor as the target inductor simplifies the modulator's structure compared to setting a physical target inductor in the modulator.

[0017] In one alternative implementation, the target capacitor includes the parasitic capacitance of the target inductor. Using the parasitic capacitance of the target inductor as the target capacitor simplifies the modulator's structure compared to setting a physical target capacitor within the modulator.

[0018] In one alternative implementation, the resistance values ​​of both the first matching resistor and the second matching resistor are R1 = Z. odd +Δ1. Where Z odd Let Δ1 be the odd-mode impedance of the transmission line, and Δ1 be the first process tolerance.

[0019] In the embodiments of this application, Z odd Odd-mode components used to match differential signals in transmission lines.

[0020] In one alternative implementation, the resistance value of the target resistor is... Among them, Z odd Z is the odd-mode impedance of the transmission line. even Δ2 represents the even-mode impedance of the transmission line, and Δ2 represents the second process tolerance.

[0021] In the embodiments of this application, It is used to match the even-mode components of the differential signal in the transmission line, thereby reducing signal reflection in the transmission line, suppressing reverse electrical signals, and increasing the modulation bandwidth of the modulator.

[0022] In one alternative implementation, the substrate of the optical waveguide includes at least one of silicon-on-insulator (i.e., silicon-based), indium phosphide (InP), and lithium niobate.

[0023] In one alternative implementation, the target resistor includes at least one of the following: metal-insulator-metal capacitor (MIMC), titanium nitride (TiN), depletion layer of a PN junction, and chip resistor.

[0024] Secondly, embodiments of this application provide an electro-optic coherent modulator, including the electro-optic modulator described in the first aspect.

[0025] Thirdly, embodiments of this application provide a chip including the electro-optic modulator described in the first aspect or the electro-optic coherent modulator described in the second aspect.

[0026] Fourthly, embodiments of this application provide an optical transmitter, including the electro-optic modulator described in the first aspect or the electro-optic coherent modulator described in the second aspect.

[0027] Fifthly, embodiments of this application provide an optical transmission network including the optical transmitter described in the fourth aspect.

[0028] The beneficial effects of aspects two through five are described in aspect one, and will not be repeated here. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the application network of this application;

[0030] Figure 2 This is a schematic diagram of the electro-optic modulator structure of this application;

[0031] Figure 3 A schematic diagram of the structure of an electro-optic modulator provided in an embodiment of this application;

[0032] Figure 4 This is a schematic diagram of the structure of an electro-optic modulator with a target resistor grounded, provided in an embodiment of this application.

[0033] Figure 5 A schematic diagram of the structure of an electro-optic modulator including a target capacitor provided in an embodiment of this application;

[0034] Figure 6 A schematic diagram of the RC matching network provided in an embodiment of this application;

[0035] Figure 7 Schematic diagram of the multilayer metal structure and waveguide doped structure provided in the embodiments of this application;

[0036] Figure 8 A schematic diagram of the structure of an electro-optic modulator including a target inductor provided for an embodiment of this application;

[0037] Figure 9 A schematic diagram of an RL matching network provided in an embodiment of this application;

[0038] Figure 10a A schematic diagram of an electro-optic modulator including a target capacitor and a target inductor, provided for an embodiment of this application;

[0039] Figure 10b Another schematic diagram of an electro-optic modulator including a target capacitor and a target inductor provided for an embodiment of this application;

[0040] Figure 11 A schematic diagram of the RLC matching network provided in an embodiment of this application;

[0041] Figure 12 This is a schematic diagram of an electro-optic coherent modulator provided in an embodiment of this application. Detailed Implementation

[0042] The embodiments of this application will now be described with reference to the accompanying drawings. Those skilled in the art will recognize that, with technological advancements and the emergence of new scenarios, the technical solutions provided in the embodiments of this application are equally applicable to similar technical problems.

[0043] The terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms are interchangeable where appropriate; this is merely a way of distinguishing objects with the same attributes in the embodiments of this application. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, so that a process, method, system, product, or apparatus that comprises a series of units is not necessarily limited to those units, but may include other units not explicitly listed or inherent to those processes, methods, products, or apparatuses. Additionally, "at least one" means one or more, and "more than one" means two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or multiple items. For example, at least one of a, b, or c can be expressed as: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple.

[0044] Please see Figure 1 , Figure 1 This is a schematic diagram of the application network in an embodiment of this application, such as... Figure 1 As shown, the network includes an optical transmitter, an optical receiver, and optical fibers. The optical transmitter performs electro-optic modulation to carry the signal in the optical fiber and transmits the optical signal through the optical fiber. The optical fiber is used to transmit the optical signal, and the optical receiver is used to receive and interpret the optical signal.

[0045] In optical transmitters, electro-optic modulation is achieved using electro-optic modulators. A commonly used electro-optic modulator structure is a differential-driven structure. For example... Figure 2As shown, the electro-optic modulator with a differential drive structure includes a transmission line and an optical waveguide. The transmission line includes a signal input terminal, a positive electrode, a negative electrode, and a matching resistor. The PN junctions on the two branches of the waveguide are coupled to the positive and negative electrodes, respectively. The signal input terminal is used to input a positive electrical signal (differential positive signal) and a negative electrical signal (differential negative signal) to the positive and negative electrodes, respectively. Continuous light is split into two beams after being input into the modulator, and input to the two branches of the optical waveguide, respectively. The two branches receive the differential positive signal and the differential negative signal, respectively. After the continuous light on the two branches is modulated, the optical signal is obtained through beam combining interference.

[0046] If the positive and negative electrodes are close together (e.g., in a coplanar stripline (CPS) structure), crosstalk may occur in the differential electrical signal between the two electrodes. For example, if the two electrodes are close together, odd-mode and even-mode electrical signals will be generated, resulting in crosstalk in the differential electrical signal. Currently, odd-mode electrical signals can be suppressed by connecting a matching resistor in series between the positive and negative electrodes, but there is no effective method to suppress even-mode electrical signals. The presence of even-mode electrical signals leads to common-mode noise between the positive and negative electrodes, i.e., common-mode noise in the differential electrical signal. When an optical waveguide electro-optically modulates a differential electrical signal with common-mode noise, the resulting optical signal will also be noisy, leading to a decrease in the efficiency and bandwidth of the electro-optic modulation.

[0047] To address the aforementioned shortcomings, embodiments of this application provide an electro-optic modulator 3000 and related devices, which achieve good impedance matching by adding a target resistor, suppressing crosstalk between the positive and negative electrodes, reducing common-mode noise, thereby improving the efficiency and bandwidth of electro-optic modulation.

[0048] The electro-optic modulator 3000 provided in this application embodiment can be exemplarily applied to the structure of a traveling-wave Mach-Zehnder modulator (TW-MZM). Therefore, in this application embodiment, the electro-optic modulator 3000 can also be referred to as TW-MZM 3000. Besides TW-MZM, the electro-optic modulator 3000 can also be other types of modulators, such as in-phase quadrature (IQ) modulators based on TW-MZM, etc., and this application does not limit this to any particular type.

[0049] like Figure 3As shown, the electro-optic modulator 3000 provided in this embodiment includes a transmission line 3100 and an optical waveguide 3200. The transmission line 3100 includes a positive electrode 3110, a negative electrode 3120, a first matching resistor 3130, a second matching resistor 3140, a target resistor 3150, and a signal input terminal 3160. One end of the positive electrode 3110 is connected to the signal input terminal 3160, and the other end is connected to the target resistor 3150 through the first matching resistor 3130. One end of the negative electrode 3120 is connected to the signal input terminal 3160, and the other end is connected to the target resistor 3150 through the second matching resistor. The first matching resistor 3130 and the second matching resistor 3140 are used to match the odd-mode characteristic impedance of the transmission line 3100.

[0050] The optical waveguide 3200 includes a first branch 3210 and a second branch 3220. The PN junction on the first branch 3210 is coupled to the positive electrode 3110, and the PN junction on the second branch 3220 is coupled to the negative electrode 3120. The two ends of the first branch 3210 and the two ends of the second branch 3120 are interconnected.

[0051] The positive electrode 3110 is used to receive a positive electrical signal (differential positive signal) from the signal input terminal 3160, and the negative electrode 3120 is used to receive a negative electrical signal (differential negative signal) from the signal input terminal 3160. Optionally, the positive and negative electrical signals can have the same amplitude but a 180° phase difference. In this embodiment, the positive and negative electrical signals are also referred to as differential electrical signals. The optical waveguide 3200 of the continuous light input electro-optic modulator 3000 is divided into two continuous light beams. One continuous light beam is input into the first branch 3210, and the other continuous light beam is input into the second branch 3220. The PN junction on the first branch 3210 receives the differential positive signal, and the PN junction on the second branch 3220 receives the differential negative signal. After the continuous light on the two branches is modulated by the PN junction, the optical signal is obtained through beam combining interference, thereby realizing electro-optic modulation.

[0052] The target resistor 3150 is used to match the even-mode characteristic impedance of the transmission line 3100, thereby suppressing common-mode noise in the transmission line 3100, reducing signal crosstalk in the transmission line, and improving the modulation bandwidth of the modulator.

[0053] If the distance between the positive electrode 3110 and the negative electrode 3120 is too close, an even-mode electrical signal may be generated on the transmission line 3100. In this embodiment, a target resistor 3150 is added to match the even-mode characteristic impedance of the transmission line 3100, thereby suppressing the even-mode electrical signal generated on the transmission line 3100.

[0054] Even-mode electrical signals include positive even-mode signals and reverse even-mode signals. Specifically, the electrical signal reflected back to signal input terminal 3160 after the differential electrical signal propagates from signal input terminal 3160 towards positive electrode 3110 (or negative electrode 3120) is called the reverse even-mode electrical signal (also referred to in this application as the reverse electrical signal from the first matching resistor 3130 to signal input terminal 3160 and the reverse electrical signal from the second matching resistor 3140 to signal input terminal 3160). The induced electrical signal generated on negative electrode 3120 by the differential positive signal on positive electrode 3110, and the induced electrical signal generated on positive electrode 3110 by the differential negative signal on negative electrode 3120, are both called positive even-mode electrical signals. Both reverse even-mode and positive even-mode electrical signals belong to common-mode noise.

[0055] This embodiment uses a target resistor 3150 to match the even-mode characteristic impedance, thereby suppressing the even-mode electrical signal. Suppressing the even-mode electrical signal suppresses both the reflection of the differential electrical signal (i.e., suppressing the reverse even-mode electrical signal) and the induced electrical signal on the positive and negative electrodes (3110 and 3120) (i.e., suppressing the forward even-mode electrical signal). Suppressing both the forward and reverse even-mode electrical signals reduces signal crosstalk in the transmission line 3100, thus suppressing common-mode noise. This reduces the noise of the differential electrical signal in the input optical waveguide 3200, further reducing the noise of the optical signal obtained from electro-optic modulation and improving the signal-to-noise ratio and electro-optic modulation bandwidth of the electro-optic modulator 3000.

[0056] Optionally, the resistance values ​​of both the first matching resistor 3130 and the second matching resistor 3140 can be R1 = Z. odd +Δ1. Where Z odd Z represents the odd-mode impedance of transmission line 3100, and Δ1 represents the first process tolerance. odd Odd-mode components used to match differential electrical signals in transmission lines.

[0057] Optionally, the target resistor value of 3150 can be... Among them, Z odd Z is the odd-mode impedance of transmission line 3100. even Δ2 represents the even-mode impedance of transmission line 3100, and Δ2 represents the second process tolerance. It is used to match the even-mode components of differential electrical signals in transmission lines, thereby suppressing common-mode noise, reducing signal crosstalk in transmission lines, and increasing the modulation bandwidth of the modulator.

[0058] In the embodiments of this application, the target resistor 3150 can exist in various forms, such as a physical resistor, the parasitic resistance of a wire, the parasitic resistance of a capacitor or inductor, etc. This application does not limit it, and will be described in detail below.

[0059] Optionally, the target resistance can be the parasitic resistance of the wire. For example... Figure 4 As shown, in the electro-optic modulator 3000, the first matching resistor 3130 and the second matching resistor 3140 can be grounded via a wire. The target resistor 3150 may include the parasitic resistance of the wire.

[0060] Optionally, the electro-optic modulator can also use a target capacitor to suppress DC signal leakage, thereby reducing the power consumption of the electro-optic modulator 3000. For example... Figure 5 As shown, the electro-optic modulator 3000 may further include a target capacitor 3170. The target capacitor 3170 is connected to a first matching resistor 3130 and a second matching resistor 3140, and / or, the target capacitor 3170 is connected to a target resistor 3150. For example... Figure 5 As shown, the target capacitor 3170 is connected to the first matching resistor 3130, the second matching resistor 3140, and the target resistor 3150. Optionally, in Figure 5 In this application, the target capacitor 3170 can also be located to the right of the target resistor 3150, and this application does not limit this.

[0061] The target capacitor 3170 is used to match the imaginary part of the even-mode characteristic impedance of the transmission line 3100. Since the capacitor has the function of blocking DC, the target capacitor 3170 can be used to suppress the leakage of DC signals in the transmission line 3100.

[0062] In this embodiment, the leakage of DC signal in the transmission line is suppressed by using a target capacitor. This reduces the power consumption of the electro-optic modulator 3000 and increases the signal strength in the transmission line, thereby increasing the signal strength in the optical waveguide and improving the electro-optic modulation conversion efficiency.

[0063] Optionally, the target resistor 3150 and the target capacitor 3170 can also be grounded to ensure that the target capacitor 3170 suppresses DC signal leakage in the transmission line 3100, reducing the power consumption of the electro-optic modulator 3000 and improving the conversion rate of electro-optic modulation. In the electro-optic modulator 3000, the target resistor 3150 is used to match the real part of the even-mode characteristic impedance of the transmission line 3100 (i.e., the real part of the interference signal impedance), and the target capacitor 3170 is used to match the imaginary part of the even-mode characteristic impedance of the transmission line 3100 (i.e., the imaginary part of the interference signal impedance). This can reduce the reflection of electrical signals in the transmission line 3100, effectively suppress reverse electrical signals, and thus improve the efficiency and bandwidth of electro-optic modulation.

[0064] Optionally, in the electro-optic modulator 3000 provided in the embodiments of this application, the target resistor 3150 may be the parasitic resistance of the target capacitor 3170; or, the target capacitor 3170 may be the parasitic capacitance of the target resistor 3150, and this application does not limit this.

[0065] Since the electro-optic modulator 3000 matches the even-mode characteristic impedance of the transmission line through the target resistor 3150(R) and the target capacitor 3170(C), the circuit of the electro-optic modulator 3000 (i.e., the transmission line 3100) is also called an RC matching network. The layout of the RC matching network is shown below. Figure 6 As shown.

[0066] Optionally, the on-chip resistors of the electro-optic modulator 3000 (such as the first matching resistor 3130, the second matching resistor 3140, and the target resistor 3150) can be implemented using doped silicon waveguides. The on-chip capacitors of the electro-optic modulator 3000 (such as the target capacitor 3170) can be implemented using metal-insulator-metal capacitors (MIMC).

[0067] Optionally, the electro-optic modulator 3000 in this embodiment can be implemented using silicon photonics technology. The multilayer metal structure and waveguide doped structure of the electro-optic modulator 3000 are as follows: Figure 7 As shown in Figures a and b.

[0068] like Figure 7 As shown in Figure a, M1, M2, and M3 are multilayer metals, each of which can be wired through methods such as spraying, epitaxy, and etching. The surface metal (M3) can be aluminum (Al), used for input or output electrical signals (e.g., RF signals, DC voltage, DC current, etc.); the inner metal (M1) can be copper (Cu), etc. The inner metal can be connected to the optical waveguide 3200 or to the TiN metal above the optical waveguide 3200 to form resistors (e.g., first matching resistor 3130, second matching resistor 3140, target resistor 3150, etc.). If the multilayer metals (such as M1 and M2) overlap horizontally but are not vertically connected by any metal, this structure can be used as an on-chip vertical MIMC, thus functioning as a capacitor (e.g., target capacitor 3170, etc.).

[0069] In the waveguide doped structure of the electro-optic modulator 3000, the substrate can be silicon-on-insulator, and waveguide doping is achieved through ion implantation. For example, phosphorus and boron can be implanted into the P-region and N-region, respectively. Alternatively, as... Figure 7 As shown in Figure b, the highly doped regions (P++ and N++) can be used to make ohmic contacts with the metal layer to realize the input or output of electrical signals; the low-doped regions (P and N) can form PN junctions (e.g., a PN junction coupled to the positive electrode 3110 on the first branch 3210, or a PN junction coupled to the negative electrode 3120 on the second branch 3220). Optionally, the depletion layer of the PN junction can also be used as a resistor, for example, the first matching resistor 3130, the second matching resistor 3140, and the target resistor 3150 can all be depletion layers of the PN junction.

[0070] Optionally, besides the silicon photonics integration platform, the electro-optic modulator 3000 can also be implemented using other processes, such as an indium phosphide platform, etc., which is not limited in this application. Accordingly, the embodiments of this application are not limited to the substrate of the optical waveguide 3200. In addition to silicon on insulator, it can also be indium phosphide (InP), lithium niobate (LiNbO3), lithium niobate single crystal thin film (LNOI) (also known as thin film lithium niobate), etc.

[0071] Optionally, in the electro-optic modulator 3000, leakage of the AC signal can also be suppressed by using a target inductor, thereby improving the electro-optic modulation bandwidth of the electro-optic modulator 3000. For example... Figure 8 As shown, the electro-optic modulator 3000 may further include a target capacitor 3180. The target inductor 3180 is connected to a first matching resistor 3130 and a second matching resistor 3140, and / or, the target inductor 3180 is connected to a target resistor 3150. For example... Figure 8 As shown, the target inductor 1380 is connected to the first matching resistor 3130, the second matching resistor 3140, and the target resistor 3150. Optionally, in Figure 8 In this application, the target inductor 1380 can also be located to the right of the target resistor 3150, and this application does not limit this.

[0072] The target inductor 1380 is used to match the imaginary part of the even-mode characteristic impedance of the transmission line 3100. Since inductors have the function of blocking AC, the target inductor 1380 can be used to suppress the leakage of AC signals in the transmission line 3100.

[0073] In this embodiment, by using the target inductor 3180 to suppress the leakage of AC signals in the transmission line 3100, the amplitude of the high-frequency electrical signals on the transmission line 3100 can be increased, thereby increasing the amplitude of the high-frequency optical signals generated on the optical waveguide 3200 and achieving an increase in bandwidth.

[0074] Optionally, the target resistor 3150 and the target inductor 1380 can also be grounded to ensure that the target inductor 3180 can leak AC signals in the transmission line 3100, thereby improving the bandwidth of electro-optic modulation. In the electro-optic modulator 3000, the target resistor 3150 is used to match the real part of the even-mode characteristic impedance of the transmission line 3100 (i.e., the real part of the interference signal impedance), and the target capacitor 3170 is used to match the imaginary part of the even-mode characteristic impedance of the transmission line 3100 (i.e., the imaginary part of the interference signal impedance). This can reduce the reflection of electrical signals in the transmission line 3100, effectively suppress reverse electrical signals, and thus improve the efficiency and bandwidth of electro-optic modulation.

[0075] Optionally, in the electro-optic modulator 3000 provided in the embodiments of this application, the target resistor 3150 may be the parasitic resistance of the target inductor 1380; or, the target inductor 1380 may be the parasitic inductance of the target resistor 3150. This application does not limit this.

[0076] Since the electro-optic modulator 3000 matches the even-mode characteristic impedance of the transmission line through the target resistor 3150(R) and the target inductor 3180(L), the circuit of the electro-optic modulator 3000 (i.e., the transmission line 3100) is also called an RL matching network. The layout of the RL matching network is shown below. Figure 9 As shown. Optionally, the target inductor 3180 can be as follows: Figure 11 As shown, it is achieved through planar spiral metal wires. In addition to planar spiral metal wires, the target inductance 3180 can also be achieved through parasitic inductance, gold wire traces, etc., and this application does not limit it in this way.

[0077] Optional, Figure 5 and Figure 6 The target capacitor 3170 shown is... Figure 7 and Figure 8 The target inductor 3180 shown can also appear in the same electro-optic modulator 3000, with the specific structure as follows: Figure 10a As shown. It is worth noting that, Figure 10a This is merely an example of the connection relationship between the target resistor 3150, the target inductor 3180, and the target capacitor 3170. These three devices can also be connected in series in other orders or in other forms (e.g., Figure 10b The T-type connection shown, etc. Figure 10b V in DD (For bias voltage), it can be connected between the first matching resistor 3130 and the second matching resistor 3140, and this application does not limit it.

[0078] Since the electro-optic modulator 3000 matches the even-mode characteristic impedance of the transmission line 3100 through a target resistor 3150 (R), a target capacitor 3170 (C), and a target inductor 3180 (L), the circuit of the electro-optic modulator 3000 (i.e., the transmission line 3100) is also called an RLC matching network. The layout of the RLC matching network is shown below. Figure 11 As shown.

[0079] exist Figure 10a or Figure 10b In the electro-optic modulator 3000 shown, reverse electrical signals can be suppressed by the target resistor 3150, leakage of DC signals in the transmission line can be suppressed by the target capacitor, and leakage of AC signals in the transmission line 3100 can be suppressed by the target inductor 3180, thereby improving the efficiency and bandwidth of electro-optic modulation.

[0080] This application also provides an electro-optic coherent modulator. For example... Figure 12 As shown, the electro-optic coherent modulator 1200 includes an optical waveguide, two electro-optic modulators 3000, and two electrical drivers. Two branches of the optical waveguide of the electro-optic coherent modulator 1200 are respectively connected to the optical waveguides 3200 of the two electro-optic modulators 3000. The two electrical drivers are respectively connected to the signal input terminal 3160 of one electro-optic modulator 3000, providing a positive electrical signal (RF+) to the positive electrode 3110 of the electro-optic modulator 3000 and a negative electrical signal (RF-) to the negative electrode 3120 of the electro-optic modulator 3000.

[0081] The two electro-optic modulators 3000 on the electro-optic coherent modulator 1200 are used to acquire the I-channel (in-phase) optical signal and the Q-channel (quadrature) optical signal, respectively. After the I-channel optical signal and the Q-channel optical signal are phase-shifted, orthogonal coherent optical signals can be obtained.

[0082] Among them, the electro-optic modulator 3000 on the electro-optic coherent modulator 1200 can be... Figures 3 to 11 The electro-optic modulator 3000 described in any of the embodiments.

[0083] This application also provides a chip, including... Figures 3 to 11 The electro-optic modulator 3000 described in any of the embodiments, or Figure 12 The electro-optic coherent modulator 1200 shown is shown.

[0084] This application also provides an optical transmitter, including... Figures 3 to 11 The electro-optic modulator 3000 described in any of the embodiments, or Figure 12 The electro-optic coherent modulator 1200 shown is shown.

[0085] Will Figures 3 to 11 The electro-optic modulator 3000 described in any of the embodiments or Figure 12 The electro-optic coherent modulator 1200 shown is used in Figure 1 The optical transmitter in the network shown is the optical transmission network provided in the embodiments of this application.

[0086] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0087] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection between apparatuses or units through some interfaces, and may be electrical, mechanical, or other forms.

[0088] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0089] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0090] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

Claims

1. An electro-optic modulator, characterized in that, include: A transmission line includes a positive electrode and a negative electrode; one end of the positive electrode is connected to a signal input terminal, and the other end is connected to a target resistor through a first matching resistor; one end of the negative electrode is connected to the signal input terminal, and the other end is connected to the target resistor through a second matching resistor; the first matching resistor and the second matching resistor are used to match the odd-mode characteristic impedance of the transmission line. An optical waveguide includes a first branch and a second branch, wherein the PN junctions on the first branch and the second branch are coupled to the positive electrode and the negative electrode, respectively; the two ends of the first branch and the two ends of the second branch are interconnected. The target resistor is used to match the even-mode characteristic impedance of the transmission line and to suppress reverse electrical signals from the first matching resistor and the second matching resistor to the signal input terminal.

2. The modulator according to claim 1, characterized in that, The first matching resistor and the second matching resistor are grounded via a wire, and the target resistor includes the parasitic resistance of the wire.

3. The modulator according to claim 1 or 2, characterized in that, It also includes a target capacitor connected to the first matching resistor and the second matching resistor, and / or connected to the target resistor, the target capacitor being used to match the imaginary part of the even-mode characteristic impedance of the transmission line and to suppress leakage of DC signals in the transmission line.

4. The modulator according to claim 3, characterized in that, The target capacitance includes the parasitic capacitance of the target resistor.

5. The modulator according to claim 3, characterized in that, The target resistance includes the parasitic resistance of the target capacitor.

6. The modulator according to any one of claims 1 to 5, characterized in that, It also includes a target inductor connected to the first matching resistor and the second matching resistor, and / or connected to the target resistor, the target inductor being used to match the imaginary part of the even-mode characteristic impedance of the transmission line and to suppress leakage of AC signals in the transmission line.

7. The modulator according to claim 6, characterized in that, The target inductance includes the parasitic inductance of the target resistor.

8. The modulator according to claim 6, characterized in that, The target resistance includes the parasitic resistance of the target inductor.

9. The modulator according to any one of claims 1 to 8, characterized in that, The resistance values ​​of both the first matching resistor and the second matching resistor are R1 = Z. odd +Δ1; Among them, Z odd Let Δ1 be the odd-mode impedance of the transmission line, and Δ1 be the first process tolerance.

10. The modulator according to any one of claims 1 to 9, characterized in that, The resistance value of the target resistor is Among them, Z odd Z is the odd-mode impedance of the transmission line. even Δ2 is the even-mode impedance of the transmission line, and Δ2 is the second process tolerance.

11. The modulator according to any one of claims 1 to 10, characterized in that, The substrate of the optical waveguide includes at least one of silicon-on-insulator, indium phosphide (InP), and lithium niobate.

12. The modulator according to any one of claims 1 to 11, characterized in that, The target resistor includes at least one of the following: the parasitic resistance of a metal-insulator-metal capacitor (MIMC), titanium nitride (TiN), the depletion layer of a PN junction, and a surface mount resistor.

13. An electro-optic coherent modulator, characterized in that, The electro-optic modulator includes any one of claims 1 to 12.

14. A chip, characterized in that, Includes the electro-optic modulator according to any one of claims 1 to 12 or the electro-optic coherent modulator according to claim 13.

15. An optical transmitter, characterized in that, Includes the electro-optic modulator according to any one of claims 1 to 12 or the electro-optic coherent modulator according to claim 13.

16. An optical transmission network, characterized in that, Includes the optical transmitter as described in claim 15.

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