Devices and methods for calibration, monitoring, and control of integrated photonic systems

Abstract

To solve problems arising from the limitations and constraints of electronic devices. [Solution] A device and method comprising: a photodetector having a waveguide; two metal layers connected to the photodetector; a measuring device connected between the two metal layers for measuring an electrical parameter between the two metal layers, wherein the electrical parameter indicates the amount of light propagating through the waveguide; and a voltage source connected between the two metal layers, wherein applying a voltage between the two metal layers changes the refractive index of the waveguide, thereby affecting the phase of light propagating through the waveguide, and the voltage to be applied is determined according to the resistance measured by a resistance measuring device.

Description

[Technical Field]

[0001] This disclosure generally relates to photonic systems, and more particularly to methods and devices for calibrating, monitoring, and controlling photonic devices. [Background technology]

[0002] Photonics is the physical science of generating, detecting, and manipulating light (photons) through emission, transmission, modulation, signal processing, switching, amplification, and sensing.

[0003] Photonic systems are becoming increasingly prevalent in all fields, though not limited to, including light detection, telecommunications, information processing, photonic computing, lighting, metrology, spectroscopy, holography, medicine (surgery, vision correction, endoscopy, health monitoring), biophotonics, military technology, laser material processing, art diagnostics, materials processing, art diagnostics with infrared reflectography (X-ray, ultraviolet fluorescence, XRF), agriculture, and robotics.

[0004] Some important applications of photonic systems include transmitting and receiving information, and multiplexing and demultiplexing information. Photonic devices may include, but are not limited to, photodetectors including photodiodes or phototransistors, laser diodes, light-emitting diodes, solar cells and photovoltaic cells, displays, and optical amplifiers. Other examples include devices for modulating light beams, and for combining and separating light beams of different wavelengths. [Overview of the project] [Problems that the invention aims to solve]

[0005] The need for photonic devices arises from the limitations and constraints of electronic devices. The first limitation is due to the saturation of electronic speeds with respect to the information transfer rate. The second limitation stems from the high power consumption of electronic devices and, consequently, the heat and cost generated. The use of photonic devices provides higher rates with little to no heating, thus solving or facilitating these problems. [Means for solving the problem]

[0006] An exemplary embodiment of the subject matter disclosed is a device comprising: a photodetector having a waveguide; two metal layers connected to the photodetector; a measuring device connected between the two metal layers for measuring an electrical parameter between the two metal layers, wherein the electrical parameter indicates the amount of light propagating through the waveguide; and a voltage source connected between the two metal layers, wherein applying a voltage between the two metal layers changes the refractive index of the waveguide, thereby affecting the phase of light propagating through the waveguide, and the voltage to be applied is determined according to the resistance measured by a resistance measuring device. In this device, the photodetector optionally further comprises a p-doped region, an n-doped region, and a waveguide intrinsic region, and the device further comprises a second p-doped region and a second n-doped region, wherein the second p-doped region and the second n-doped region are doped to a higher level than the p-doped region and the n-doped region. Within this device, the device is optionally placed on a silicon dioxide layer placed on a silicon layer. Within this device, the values ​​of electrical parameters are optionally measured to evaluate the parameters of the photodetector. Within this device, the values ​​of electrical parameters are optionally measured to evaluate the amount of light passing through the photodiode, and voltage is applied to control the amount of light. Within this device, the electrical parameters are optionally resistance or conductance. Within this device, the measuring device is optionally an ohmmeter or an amperemeter.

[0007] Another aspect of the present disclosure is a method for generating a calibration model for a device, system, or subsystem, comprising: obtaining indications of control parameters affecting the behavior of the device, system, or subsystem; obtaining a plurality of sets of values, each set of values ​​containing input parameter values; obtaining values ​​to be applied and applying those values ​​to the control parameters; measuring values ​​of output parameters of the device, system, or subsystem obtained in response to the application of the control parameter values; determining a calibration model for the device, system, or subsystem based on at least one set of measured input parameters, applied values ​​of the control parameters, and values ​​of the output parameters; and storing the calibration model. The method may further include obtaining one or more characteristics for the control parameters, the characteristics being selected from a group consisting of value ranges and resolutions. The method may further include measuring the impulse response of a circuit. The method may further include measuring the relaxation time of a photocarrier. Within the method, the calibration model is optionally further based on a physical model of the device, system, or subsystem. Within this method, the calibration model may optionally be further based on a mathematical model of the device, system, or subsystem.

[0008] Another aspect of this disclosure is a method for calibrating a device, system, or subsystem, comprising receiving a value for an input parameter, receiving a required value for an output parameter, determining a value for a control parameter to be applied to obtain the required value for the output parameter using a calibration model of the device, system, or subsystem, and storing the calibration model. In this method, one of the input parameters is optionally temperature, one of the control parameters is optionally a phase shifter voltage, and one of the output parameters is optionally a resistance or conductance indicating the phase of light propagating through a waveguide. In this method, the resistance or conductance optionally indicates the phase of light propagating through a waveguide. The method is optionally performed offline.

[0009] Another aspect of this disclosure is a method for monitoring and controlling a device, system, or subsystem, comprising receiving a measured value of an input parameter, obtaining a value for at least one control parameter from a model of the device, system, or subsystem in order to obtain a required value of an output parameter of the device, system, or subsystem, and applying the value of at least one control parameter. In this method, one of the input parameters is optionally temperature, one control parameter is optionally a phase shifter voltage, and one of the output parameters is optionally resistance or conductance. In this method, resistance or conductance optionally indicates the phase of light propagating through a waveguide. The method is optionally performed online. In this method, the device, system, or subsystem is optionally operated initially with values ​​for the control parameter determined during an offline calibration step.

[0010] The subject matter disclosed will be better understood and appreciated from the following detailed description, accompanied by drawings, where corresponding or similar numbers or letters indicate corresponding or similar components. Unless otherwise specified, the drawings provide exemplary embodiments or aspects of the disclosure and do not limit the scope of the disclosure. [Brief explanation of the drawing]

[0011] [Figure 1] This figure shows an example of a coherent optical transceiver that uses multiple photonic devices. [Figure 2] This figure shows a device that provides a photonic implementation of a convolutional neural network (CNN) that implements the broadcast-and-weight protocol. [Figure 3] This is a schematic diagram of the structure of an integrated optical finite impulse response (FIR) lattice filter. [Figure 4] This is a schematic diagram of a transmitter using TDM according to some exemplary embodiments of the present disclosure. [Figure 5] This is a schematic diagram of a receiver corresponding to the transmitter in Figure 4, according to some exemplary embodiments of the present disclosure. [Figure 6] This is a schematic diagram of another transmitter using all-optical multiplexing, according to some exemplary embodiments of the present disclosure. [Figure 7] This is a schematic diagram of a receiver corresponding to the transmitter in Figure 6, according to some exemplary embodiments of the present disclosure. [Figure 8] This is a schematic diagram of a device for monitoring and controlling a photonic device, according to some embodiments of the present disclosure. [Figure 9] Figure 8 is a schematic circuit diagram in which the device may be used in some embodiments of the present disclosure. [Figure 10]Schematic diagram of an entity related to a calibration model of a device, system, or subsystem according to some embodiments of the present disclosure. [Figure 11] Flowchart of a method for generating a calibration model of a device according to some embodiments of the present disclosure. [Figure 12] Flowchart of a method for creating and using a calibration model according to some embodiments of the present disclosure.

Mode for Carrying Out the Invention

[0012] Photonics relates to the generation, detection, and manipulation of light through emission, transmission, modulation, signal processing, switching, amplification, and detection.

[0013] Photonic systems are becoming increasingly popular in multiple applications in various fields.

[0014] The need for photonic devices arises from the limitations and restrictions of electronic devices, including the information transfer rate and the high power consumption of electronic devices, and thus the heat and cost generated.

[0015] The use of photonic devices reduces these problems, but photonic devices also have problems. The first problem can be their physical size. The size of electronic devices can be on the order of a few nanometers, but the size of current photonic devices is on the order of tens of micrometers. Their relatively large size also increases the sensitivity of the device to manufacturing problems, for example, due to variations in the manufacturing process between different areas of the same device.

[0016] Another problem with photonic devices is their remarkable sensitivity to size or shape deviations, and to environmental conditions such as temperature changes. Therefore, slight deviations in the manufacturing process, or temperatures slightly different from those intended, can lead to components that are not of the designed size, thus significantly reducing their functionality.

[0017] Therefore, in some circuits, some electronic devices can be replaced with photonic devices if the trade-off is positive. For example, photonic devices may be used when a high rate is required, but not when multiple components are needed and the available physical area is limited.

[0018] Next, see Figure 1, which shows an example of a coherent optical transceiver that uses multiple photonic devices to decode the received wavelength 104 according to an electrical signal 108 and transmit it to a corresponding receiver via a full-duplex fiber 112, and vice versa.

[0019] If any component behaves differently than expected due to manufacturing variations, temperature effects, or other reasons, the resulting signal will not be what is expected, and the system's performance will degrade.

[0020] Refer to Figure 2, which shows another example of a device that provides a photonic implementation form of a convolutional neural network (CNN) that implements a broadcast-and-wait protocol. This design includes two or more micro-ring resonators (MRRs) 212, 216, 220, and 224, as well as photodiodes such as 228, 232. The MRRs perform multiply-and-accumulate (MAC) operations, and the broadcast-and-wait protocol carries the MAC results across the layers. In the broadcast-and-wait protocol, each neuron output is transmitted using a laser diode (LD) to λ1...λ n These are multiplexed onto separate optical wavelengths. The multiplexed wavelengths are bundled together by wavelength division multiplexing 236 and placed on a waveguide for broadcast to the destination layer.

[0021] In the destination layer, each neuron receives all incoming wavelengths. Each wavelength is then multiplied in amplitude using its corresponding micro-ring. The multiplication is performed by tuning the ring to resonant and non-resonant states for each laser wavelength. Subsequently, a photodiode sums all incoming wavelengths to form an aggregate photocurrent.

[0022] It will be understood that each ring, such as 212, 216, 220, and 224, resonates at wavelengths whose outer circumference is an integer multiple of those wavelengths, thereby creating constructive interference.

[0023] Therefore, for example, slight variations in the diameter of one or more rings due to manufacturing deviations or temperature changes may cause the rings to fail to transmit the correct wavelength and not provide the expected constructive interference. Consequently, the device may not output the expected output.

[0024] There may be several further examples demonstrating the sensitivity of systems incorporating photonic devices, such as silicon optical filters reconstructed from Benes switch matrices of various sizes.

[0025] It will be understood that the more photonic devices a circuit has, for example, the larger the Benes switch matrix, the more sensitive the circuit becomes, as errors can accumulate and lead to reflections, destructive interference, or other problems.

[0026] Figure 3 shows a schematic diagram of an integrated optical finite impulse response (FIR) grating filter implemented by cascading symmetric and asymmetric Mach-Zehnder interferometers (MZIs), where MZIs with arms of equal length are denoted as symmetric MZIs, and MZIs with arms of different lengths are denoted as asymmetric MZIs. Using tunable phase-shift elements on the MZI arms, a symmetric MZI is a variable coupler that controls the amount of energy directed to the upper or lower arm. An asymmetric MZI is a fixed-delay and variable-phase-shift element. Using this type of filter structure, an FIR grating filter with variable complex coefficients is obtained. The filter order is determined by the number of cascaded symmetric and asymmetric MZI pairs. In a filter of order 1, symmetric MZIs must be interleaved by asymmetric MZIs. This filter is a photonic device sensitive to manufacturing, temperature, and other variations. For proper device operation, a thermo-optic shifter 304 is used for correct phase matching.

[0027] To monitor photonic devices, some conventional methods involve splitting the energy of received light and using a portion of that light to evaluate the system's wavelength offset and phase shift. However, splitting in this way reduces the received energy, and further splitting to monitor additional components further reduces the energy, which can ultimately lead to significant energy loss. Moreover, such splitting can cause reflections that can further impair the output. Furthermore, evaluating degradation using these methods does not allow for output compensation, as the physical structure and state of the components are fixed.

[0028] Therefore, one issue of this disclosure is the need to monitor the performance of a photonic device and determine whether the photonic device provides the expected output.

[0029] Another issue of this disclosure is the need to compensate for parameters that deviate from the expected performance of such devices, for example, the phase shift of a photonic device, if a phase shift is detected, in order to ensure its proper operation.

[0030] Another issue of this disclosure is the need to evaluate and correct the behavior of photonic devices in a non-invasive manner, without affecting the device itself and without allocating any portion of the delivered energy for evaluation purposes, thereby avoiding energy waste.

[0031] Another issue of this disclosure is the need to monitor and control photonic devices using a single device rather than a first device for monitoring and a second device for control, thereby reducing the footprint of the correction device and the energy wasted.

[0032] Another issue of this disclosure is the need to monitor and control the behavior of photonic devices in the context of the circuit in which they are installed. Because interrelationships such as reflections may exist between components, different behaviors may be observed between independent photonic devices or within a circuit, and different corrections may be required.

[0033] Another issue of this disclosure is the need for a consistent method for creating calibration models for the behavior of photonic devices or systems or subsystems comprising photonic devices. Such models can then be used for monitoring and controlling the behavior of the device or circuit at runtime.

[0034] Figures 4 to 7 below show exemplary all-optical circuits for the transmitter and receiver.

[0035] Figure 4 shows a transmitter using all-optical multiplexing, operating with time-division multiplexing (TDM) via a pulsed laser, where the clock is transmitted on a polarization orthogonal to the signal. The multiplexer operates at a certain wavelength λ i It receives a pulsed laser 404, electrical input 1 (408), and electrical input 2 (412), and outputs a multiplexed channel 416 as a pulsed laser at a certain bit rate, and a clock at half that bit rate in TM mode.

[0036] Figure 5 shows a corresponding all-optical multiplexing receiver operating with time-division multiplexing (TDM) using a pulsed laser, where the clock is transmitted on a polarization orthogonal to the signal.

[0037] The transmitter-receiver pairs in Figures 4 and 5 operate by splitting the input laser pulse into data and clock signals by polarization, and therefore they do not influence each other.

[0038] Figure 6 shows a transmitter using all-optical multiplexing, operating with time-division multiplexing (TDM) via a pulsed laser using a full-duplex fiber, and Figure 7 shows the corresponding receiver.

[0039] The transmitter-receiver pair in Figures 6-7 operates by splitting the input laser pulse into data and clock signals for different fibers, thus ensuring they do not interfere with each other.

[0040] It will be understood that each of the circuits in Figures 4 to 7 comprises multiple photonic devices, and that the operation of each circuit heavily depends on the proper operation of its components. Therefore, it is important that the required components are calibrated in the context of the circuit and monitored during use. If deviations from the required behavior are detected, corrections must also be introduced.

[0041] One technical solution of this disclosure is a device for monitoring and controlling the phase of a photonic device. The monitoring device is P - The region, the waveguide through which the light to be measured propagates, and N - The device includes a PIN photodiode with a region and a region. The device is intended to create ohmic contacts, each with a P + Region and N + P through the region - Region and N - It further features two metal contacts connected to the region.

[0042] When light propagating through a waveguide creates free electrons and holes, it reduces the resistance of the device and increases its conductance. Therefore, the measurable resistance / conductance indicates the amount of light propagating. On the other hand, applying a voltage to a device changes the electron and hole concentration, thereby changing the refractive index of the waveguide. This can shift the phase of the propagating light and change its amplitude due to the effect of its phase on constructive or destructive interference. Therefore, a phase shifter can be created to monitor and control the phase of light propagating through a waveguide.

[0043] Another technical solution of this disclosure relates to the offline creation of a calibration model for a photonic device or a system or subsystem comprising a photonic device. The model may be used for the individual offline calibration of each device, including determining its operating point when a sample of the device is available.

[0044] The term "input parameter" can be broadly interpreted to include any existing parameters of a device, environment, or circuit that can be measured and affect the behavior of the device, system, or subsystem, such as temperature, jitter, or noise.

[0045] The term control parameter can be broadly interpreted to include any parameter that may be applied to a device, system, or subsystem, such as various temperatures, voltages, or currents.

[0046] The term output parameters can be broadly interpreted to include any parameters that indicate a performance factor of a device, system, or subsystem, such as the amount of light propagated or the bit error rate.

[0047] During model generation, different sets of input parameters may be provided, and different values ​​may be set for one or more control parameters. Output parameters may be measured under these conditions. The set of input parameters, control parameters, and outputs may be used by mathematical, physical, and / or AI techniques to generate the model.

[0048] In a further stage, when device samples are available, individual offline calibrations may be performed for each device. Input parameters may be measured and provided to the model, required output parameters may be taken, for example, from requirements, and values ​​for control parameters may be taken so that the device, system, or subsystem operates and provides the required output. These values ​​are sometimes called operating points.

[0049] When a device, system, or subsystem is in use and operating according to operating points determined, for example, during offline calibration, the model may receive measured values ​​of input parameters and provide values ​​for control parameters for fine control of the device, system, or subsystem in order to obtain the required values ​​of output parameters.

[0050] Improving control parameters can be carried out continuously to ensure that a device, system, or subsystem provides the required output according to existing environmental and system conditions, as well as conditions that change as needed.

[0051] In one example, a device model can be created and used in which the phase of propagating light can be controlled, as described above. In this case, the input parameter may be temperature, the control parameter is the applied voltage, and the output parameter is resistance, which indicates the amount of light.

[0052] Therefore, during calibration model generation, temperature may be measured, different voltages may be applied, and corresponding resistances may be measured. The calibration model for the device may be determined empirically, analytically, or using a combination thereof, for example, by combining the measured values ​​with a mathematical or physical model of the photonic device, in order to obtain the model. The model, which can be used for offline calibration of the device as well as for online monitoring and control, may indicate, for each measured temperature and required resistance, the required resistance and, therefore, what voltage needs to be applied to reach the required phase of the propagating light. The model, which may be represented as an analytical function, a lookup table, etc., may be provided to and stored in a microcontroller (MCU) that controls the measurement and voltage application of the device.

[0053] Another technical solution of this disclosure relates to measuring the relaxation time of photocarriers after the propagation of an optical pulse. When the optical pulse begins to propagate, the concentrations of electrons and holes increase, and then decrease during the relaxation time. The relaxation curve is influenced by material properties, such as the amount of contamination or defects in the semiconductors that make up the photonic device. Therefore, using a voltage source and a resistance measuring device can provide measurement of the relaxation time and provide information about the material properties and manufacturing process.

[0054] Another technical solution of this disclosure relates to a voltage source and a resistance or photocurrent measuring device that enable the investigation of the impulse response and transfer function of a photonic device in response to discontinuous pulses of light.

[0055] One technical effect of this disclosure is the provision of a single device that enables the calibration, monitoring, and control of one or more parameters of a photonic device, such as the optical phase of an optical phase shifter. The single device helps reduce the footprint, power consumption, installation costs, and operating costs of different devices used for monitoring and controlling photonic devices.

[0056] Another technical effect of the present disclosure is to calibrate, monitor, and control one or more photonic devices within a system or subsystem, and thus ensure that the system or subsystem operates as a whole as expected rather than operating separately for each photonic device, which could expose the system or subsystem to unexpected inter-effects that could harm its performance.

[0057] Yet another technical effect of the present disclosure is to provide for the offline generation of calibration models for monitoring and controlling a device, system, or subsystem, as well as the offline calibration of a particular device, either as an independent entity or as part of a system or subsystem, and the online monitoring and control of the device or system, or subsystem.

[0058] Yet another technical effect of the present disclosure is to provide for the investigation of additional parameters and characteristics of photonic devices and their manufacturing processes, or of systems comprising photonic devices.

[0059] Next, refer to FIG. 8, which shows a schematic diagram of a device for monitoring and controlling a photonic device according to some embodiments of the present disclosure.

[0060] The device includes a photo-detector having P - doped region 808 and N - doped region 812, and a waveguide 704 disposed therebetween, made, for example, of silicon. The photo-detector and the waveguide 704 may be disposed on a silica (S i ) layer 836 that is disposed on a silicon (S i ) substrate 832.

[0061] The device includes two metal layers 824 and 828 made, for example, of aluminum (Al), and P +Doped regions 816 and N + It also features a doped area 820. + Doped region 816 and N + Doped region 820 and P - Doped region 808 and N - It should be understood that this will be doped to a higher level than doped region 812.

[0062] The disclosed P-type-Intrinsic-N-type (PIN) structure is merely an example, and it should be understood that several other components and materials, such as rib waveguide PINs, may be used.

[0063] The device may comprise a resistance or photocurrent measuring device 832, such as an ohmmeter or amperemeter, and a voltage source 836. The ohmmeter 832 and the voltage source 836 may be connected to a microcontroller unit (MCU) 840. The ohmmeter 832 may report the measured resistance to the MCU 840.

[0064] During the offline model generation phase, the model may be generated and stored in the MCU 840. During the offline calibration phase, the model may be used to determine the correction voltage to be applied, and during the monitoring and control phase, the model may be used to determine the correction voltage to be applied so that the concentration of electrons and electron holes in the PN junction increases or decreases, thereby changing the refractive index in the waveguide 804 and changing the phase of the waveguide light by the required amount, and to provide the corresponding command to the voltage source 836.

[0065] It should be understood that the voltage can be set to reverse bias or forward bias.

[0066] The disclosed structures can be used with any required components of a device for monitoring and controlling the amount of light. For example, the pulse shaper 420 or tunable phase shifter 424 in Figure 4, the pulse shaper 604 or 608 or tunable phase shifter 612 in Figure 6, the chirp-Bragg grating 504 in Figure 5, or the chirp-Bragg grating 704 in Figure 7 can be implemented as the phase shifter shown in Figure 3. For monitoring and controlling the device, the thermo-optic phase shifter 304 in Figure 3 can be implemented as the device in Figure 8 and thus monitored and controlled.

[0067] Next, refer to Figure 9, which shows a schematic circuit in which the disclosed device may be used. The circuit, generally referred to as 900, comprises a transmitter 904 and a receiver 908, but is not limited to the transmitter and receiver in Figures 4 and 5, the transmitter and receiver in Figures 6 and 7, or any other implementation form involving a photonic device. The transmitter 904 may transmit information to channel 912, and the receiver 908 may receive information from channel 912. Thus, the transmitter 904, the receiver 908, and channel 912 can all affect the performance of the system. Therefore, it may be insufficient to evaluate the performance of one or more components of the transmitter 904 or receiver 908, or even the transmitter 904 or receiver 908 as a whole, and it may be necessary to evaluate the performance of the entire system.

[0068] The necessary values ​​to ensure the system provides the required output can be stored in the MCU916 as part of the calibration model. It will be understood that the MCU916 can be accessed via interface 120, which may include I / O devices such as a display, keyboard, mouse, or touchscreen pointing device.

[0069] Next, refer to Figure 10, which shows a schematic diagram of an entity related to generating a calibration model of a device, system, or subsystem, such as the schematic circuit in Figure 9 above, or any of the circuits in Figures 4 to 7 above. The calibration model may be generated offline, for example, during the design of the system. The model may then be used during offline calibration when the circuit is available for testing, and further used during online monitoring and control when the system is in use.

[0070] Model-based calibration and physical model 1008 can receive a set of input parameters 1004 related to the circuit and environment, such as temperature, clock jitter, and noise such as laser noise. These parameters can be measured by any suitable instrument and reported manually or automatically via a suitable interface.

[0071] During model generation, the model-based calibration and physical model 1008 may further receive instructions about controllable input parameters 1012 and their characteristics, such as range, accuracy, or resolution. For example, the parameters may include laser bias, modulator bias, phase shifter bias, TIA bias, thermoelectric cooler bias, etc., each having its own characteristics.

[0072] The applicable outputs or performance of the system may be expressed as one or more output parameters, also called response parameters, such as bit error rate, throughput, and frame loss, but are not limited to these.

[0073] The measured values ​​of input parameter 1004, the values ​​of control parameter 1012, and the value output parameter 1016 may be used by model-based calibration and physical model 1008 to generate a calibration model. A table may be created correlating the values ​​of input parameters such as temperature and jitter, controlled parameters such as V phase shifter, I laser, V modulator, or V amplifier, and output parameters such as bit error rate. Table 1 below shows an example of such a table. [Table 1]

[0074] Therefore, under conditions of a temperature of 300 degrees Kelvin and a jitter of 10 pS, 2*10 -6 The bit rate can be achieved by applying the following control parameters: a phase shifter voltage of 3V, a laser current of 20mA, a modulator voltage of 2.5V, and an amplifier voltage of 5.5V.

[0075] Table 1 is merely an example, and it should be understood that it is simply intended to demonstrate the relationship between the measured values, the controls to be applied, and the output of the circuit. In some situations, more input parameters, control parameters, or output parameters may exist. In further situations, several parameters of the same type may exist; for example, a third-order filter may require three phase shifter voltage values.

[0076] In the example of the phase shifter disclosed above, the control to be applied is voltage, and the output is a resistance that indicates the phase of the propagating light.

[0077] Next, refer to Figure 11, which shows a flowchart of a method for generating a calibration model according to some embodiments of the present disclosure.

[0078] In step 1100, a model generation process may be designed, which includes determining input parameters such as temperature, control parameters such as input voltage, and output (response) parameters such as resistance and bit error rate. Several characteristics may be determined for the input parameters, control parameters, and output parameters, such as resolution, where a higher resolution may be more accurate but may take longer due to more measurements that need to be performed and more processing time to determine the model; a feasible or recommended range of values, such as values ​​that are more energy-efficient or provide a longer service life for the device; and constraints.

[0079] It will be understood that various experimental design strategies or methodologies can be applied to reduce the time and cost of data acquisition. Some non-limiting examples of optimized designs may include A-optimal, V-optimal, D-optimal, and Sobol sequences.

[0080] In step 1104, input parameters may be measured (or optionally set, if possible), values ​​for the controlled parameters may be applied, and the resulting output measurements may be taken. For example, a voltage may be applied, the resulting resistance may be measured, and based on these measurements, an appropriate bias voltage may be determined for the required phase adjustment. The measurements may be summarized in a data structure similar to that in Table 1 above.

[0081] Based on the measurements, a model may be created in step 1108 based on discrete points, for example, represented as rows in Table 1. The model may be based on mathematical techniques such as linear or nonlinear regression, Gaussian process regression, or AI techniques such as neural networks (NN), deep NNs, shallow NNs, clustering, and dimensionality reduction.

[0082] Any known physical model of one or more devices may be used and incorporated into the model. In some embodiments, the model may be integrated, combining all controlled parameters and all output parameters. In other embodiments, for example, when some parameters are orthogonal to each other, the model may be implemented as two or more separate models, and optionally as simpler models.

[0083] In step 1112, the model may be optimized and made more accurate using, for example, mathematical techniques, computing techniques, etc. For example, the linear areas of the model may be determined and treated separately from other areas, and the nonlinear areas may require a higher resolution for the controlled parameters.

[0084] In step 1116, the model may be stored in any form, such as an expression, a lookup table, a combination thereof, or any other form. The model may be stored in the MCU or in a data storage device accessible to the MCU.

[0085] In some embodiments, if the results are unsatisfactory, for example, if the output parameters do not obtain satisfactory values, one or more devices may be redesigned. For example, in the device shown in Figure 3, the phase shift depends on the multiplication of the bias voltage and the length, and therefore the length of the device may be increased to allow for a larger phase without increasing the voltage. It will be understood that if a model is generated during the design of a device and turns out to be extremely complex with a number of parameters exceeding a predetermined number, it can be inferred that the design is suboptimal and the device, system, or subsystem needs to be redesigned.

[0086] In addition to the calibration process, additional measurements may be performed, and their results may be used to evaluate other aspects of the photonic device or system, or the manufacturing process. Such measurements may include the relaxation time of the circuit, which may provide information about material parameters and the manufacturing process, and the impulse response, which may provide information about the response function of the subsystem, circuit, or entire system.

[0087] Next, refer to Figure 12, which shows a flowchart of the method for creating and using calibration models, as generally referred to in 1200.

[0088] In step 1204, the model can be generated offline, as detailed in relation to Figure 11 above.

[0089] In step 1208, one or more devices may be calibrated offline using the model generated in step 1204. Calibration may provide adjustment of the operating point for each such device. Because photonic devices tend to be relatively large, variations in the manufacturing process can exist between devices and on each device, and can have a significant impact on their behavior. Therefore, individual calibration may be required for each such device.

[0090] In step 1212, the measured input parameters and the required output parameters may be provided to the model. It will be understood that the combination of measured input parameters and required output values ​​may not correspond to a particular case (for example, a particular row in a measurement table such as Table 1), and therefore the model may need to provide recommended values ​​for the control parameters under existing circumstances. In a simplified linear example, these values ​​may be obtained by interpolating other values ​​in the data used to generate the model.

[0091] In step 1216, the model may determine the required values ​​for the control parameters that will produce the desired output, and in step 1220, the values ​​of the control parameters may be stored in relation to a particular device. It will be understood that multiple rows in Table 1 may be used by the model to determine how the control parameters should be varied to obtain the desired output, although only a few rows may correspond to the desired output.

[0092] In step 1224, the device may be used, and online monitoring and control may be carried out in accordance with existing and changing conditions such as the circuit and environment.

[0093] The device may be brought into operation with the control parameter values ​​obtained in step 1216 of the offline calibration. In step 1228, the measured input parameters and the required output parameters may be received by the model.

[0094] In step 1232, using the received measurements and expected output values, the model may determine values ​​to be applied for control parameters to achieve the desired output, similar to step 1216 of the offline calibration. These values ​​may be those initially determined in step 1216 above, and improvements may be required due to existing and changing conditions under which the device is used.

[0095] In step 1236, the MCU may apply commands to determine or set those values, such as the required voltage between metal layers, to achieve the required output, such as the required resistance indicating the required phase of light propagating through the waveguide.

[0096] The present invention may be a system, method, and / or a computer program product. The computer program product may include a computer-readable storage medium (or media) having computer-readable program instructions thereon for causing a processor to perform aspects of the present invention.

[0097] Computer-readable storage media can be tangible devices capable of holding and storing instructions for use by instruction-executing devices. Computer-readable storage media can be, for example, but are not limited to, electronic storage devices, magnetic storage devices, optical storage devices, electromagnetic storage devices, semiconductor storage devices, or any preferred combination of the above. A non-exhaustive list of more specific examples of computer-readable storage media includes portable computer diskettes, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM) or flash memory, static random access memory (SRAM), portable compact disc read-only memory (CD-ROM), digital versatile disk (DVD), memory sticks, floppy disks, mechanically encoded devices such as punched cards or grooved raised structures on which instructions are recorded, and any preferred combination of the above. The computer-readable storage media used herein should not be interpreted as being transient signals in themselves, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through waveguides or other transmission media (e.g., light pulses passing through fiber optic cables), or electrical signals transmitted through wires.

[0098] The computer-readable program instructions described herein may be downloaded from a computer-readable storage medium to each computing / processing device, or downloaded to an external computer or external storage device via a network, such as the Internet, a local area network, a wide area network, and / or a wireless network. The network may include copper transmission cables, optical transmission fibers, wireless transmitters, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives computer-readable program instructions from the network and forwards them for storage in a computer-readable storage medium within each computing / processing device.

[0099] The computer-readable program instructions for performing the operation of the present invention may be assembler instructions, instruction-set-architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, state-setting data, or source code or object code written in any combination of one or more programming languages ​​such as "C", C#, C++, Java, Python, Smalltalk, etc. The computer-readable program instructions may run entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the latter scenario, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection may be made to an external computer (for example, via the Internet using an Internet service provider). In some embodiments, an electronic circuit, including, for example, a programmable logic circuit, a field-programmable gate array (FPGA), or a programmable logic array (PLA), may execute a computer-readable program instruction by personalizing the electronic circuit using state information of a computer-readable program instruction in order to carry out an aspect of the present invention.

[0100] Aspects of the present invention will be described herein with reference to flowcharts and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the present invention. It will be understood that each block in the flowcharts and / or block diagrams, and combinations of blocks in the flowcharts and / or block diagrams, can be implemented by computer-readable program instructions.

[0101] These computer-readable program instructions may be provided to the processor of a general-purpose computer, a dedicated computer, or other programmable data processing device for creating machines, and so the instructions executed via the processor of the computer or other programmable data processing device create means for implementing functions / actions specified in one or more blocks of a flowchart and / or block diagram. These computer-readable program instructions may also be stored in a computer-readable storage medium that can instruct computers, programmable data processing devices, and / or other devices to function in a particular manner, and so the computer-readable storage medium storing the instructions comprises a product containing instructions that implement modes of functions / actions specified in one or more blocks of a flowchart and / or block diagram.

[0102] Computer-readable program instructions can also be loaded onto a computer, another programmable device, or another device to cause a series of operational steps to be performed on the computer, another programmable device, or another device in order to create a computer implementation process; therefore, instructions executed on a computer, another programmable device, or another device implement the functions / actions specified in one or more blocks of a flowchart and / or block diagram.

[0103] The flowcharts and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in the flowchart or block diagram may represent a module, segment, or portion of instructions comprising one or more executable instructions for implementing a specified logical function. In some alternative implementations, the functions described in the blocks may be performed in a different order than that shown in the diagram. For example, two consecutively shown blocks may be executed effectively substantially simultaneously, or they may be executed in reverse order from time to time, depending on the functionality involved. It should also be noted that each block in the block diagram and / or flowchart, and combinations of blocks in the block diagram and / or flowchart, may be implemented by a dedicated hardware-based system that performs a specified function or action, or combines dedicated hardware with computer instructions.

[0104] The technical terms used herein are for illustrative purposes only and do not limit the invention. The singular forms “a,” “an,” and “the” used herein also include the plural form unless the context otherwise clearly indicates. Furthermore, the terms “comprises” and / or “comprising” used herein indicate the presence of the described features, completes, steps, actions, elements, and / or components, but do not exclude the presence or addition of one or more other features, completes, steps, actions, elements, components, and / or groups thereof.

[0105] All corresponding structures, materials, actions, and equivalents of all means-plus-function elements or step-plus-function elements in the following claims include any structures, materials, or actions for performing a function in combination with other claimed elements specifically claimed. The description of the present invention is presented for illustrative and explanatory purposes, but is not exhaustive and does not limit the invention to the disclosed forms. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the invention. The examples have been selected and described to best illustrate the principles and practical applications of the invention and to enable others skilled in the art to understand the invention for various examples with various modifications suitable for specific intended uses.

Claims

1. A device for calibrating photonic systems, A photodetector comprising a PIN junction including a p-doped region, an intrinsic silicon bulk waveguide, and an n-doped region, Two metal layers connected to the photodetector, wherein the p-doped region and the n-doped region are in contact with the intrinsic silicon bulk waveguide, and the two metal layers are not in contact with the intrinsic silicon bulk waveguide, A measuring device connected between the two metal layers for measuring the value of an electrical parameter between the two metal layers, wherein the electrical parameter indicates the amount of light propagating through the intrinsic silicon bulk waveguide, thereby performing measurements on the intrinsic silicon bulk waveguide and avoiding energy waste; A voltage source connected between the two metal layers, wherein applying a voltage between the two metal layers changes the refractive index of the intrinsic silicon bulk waveguide, thereby affecting the phase of light propagating through the intrinsic silicon bulk waveguide, and the voltage to be applied is determined according to the value measured by the measuring device. A device equipped with the following features.

2. The device according to claim 1, further comprising a second p-doped region and a second n-doped region, wherein the second p-doped region and the second n-doped region are doped to a higher level than the p-doped region and the n-doped region.

3. The device according to claim 1, wherein the device is disposed on a silicon dioxide layer disposed on a silicon layer.

4. The device according to claim 1, wherein the value of the electrical parameter is measured to evaluate the parameter of the photodetector.

5. The device according to claim 1, wherein the value of the electrical parameter is measured to evaluate the amount of light passing through the photodiode, and the voltage is applied to control the amount of light.

6. The device according to claim 1, wherein the electrical parameter is resistance or conductance.

7. The device according to claim 1, wherein the measuring device is an ohmmeter or an amperemeter.

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