13 results about "Carrier dynamics" patented technology

The invention discloses a multi-source autonomous navigation system and method with embedded carrier dynamic characteristics, and the method comprises the steps: building a carrier dynamic model in a dynamic modeling stage; in a filter prediction stage, a Kalman filter driven by dynamics is established, a carrier execution mechanism control signal is periodically read as filter input, and a state vector and a covariance matrix are predicted in each sampling period; a filter updating stage: calculating information of each sensor and a carrier maneuvering strength index, constructing a dynamics consistency judgment quantity, adaptively adjusting an observation variance matrix, updating a filtering state according to observation information of the sensor, and realizing multi-source information fusion; and a fault detection and isolation stage: constructing a multi-source consistency index, and judging the health state of the navigation system. According to the invention, the problem that the performance of a traditional navigation system is reduced when a carrier platform violently moves or is disturbed by external force of the environment is solved, and robust high-precision navigation under GNSS denial, sensor failure or complex dynamic conditions is realized.

The invention relates to an intelligent multi-source navigation method based on inertia and Beidou / visual information fusion, which comprises the following steps: firstly, establishing a multi-source information system of an inertial navigation system, and embedding an IMU (Inertial Measurement Unit) multi-parameter online calibration mechanism based on carrier dynamics in inertial navigation solution; establishing a tight coupling fusion framework taking an INS resolving result as a reference, and constructing tight combination measurement with the original observed quantity of the BDS and constructing re-projection error measurement with the visual feature points by utilizing INS high-frequency pose information; an intelligent adaptive filter based on inertial dynamics error model constraint is adopted, an INS error equation is used as a state prediction model, a Sage-Husa algorithm is introduced to estimate system noise statistical characteristics in real time, estimated error parameters are fed back to INS calculation through closed-loop correction, real-time correction of navigation results is achieved, and the system noise statistical characteristics are estimated in real time. Through deep tight coupling fusion and intelligent adaptive processing, navigation precision and system reliability in a complex environment are effectively improved.

The invention belongs to the technical field of reliability analysis of devices, and particularly relates to a quantitative analysis method for migration characteristics of an indium component in an epitaxial wafer. Comprising the following steps: providing epitaxial wafers with consistent initial characteristics, and carrying out uniform cleavage; taking one small block as a reference sample, and performing external disturbance treatment on other small blocks; the method comprises the following steps: respectively carrying out non-destructive structure characterization treatment on a reference sample and a sample subjected to external disturbance treatment, including high-resolution X-ray diffraction test, photoluminescence and cathode fluorescence combined test and time-resolved photoluminescence spectrum measurement; comprising high-resolution transmission electron microscope and EDS energy spectrum combined imaging and secondary ion mass spectrum; finally, FP lasers are prepared respectively, and electrical characterization processing is carried out. And quantitatively analyzing the influence of indium component migration on the electrical properties of the FP laser according to the result. The method has the advantages that the migration of indium atoms is analyzed according to a method for changing the microstructure in the quantum well and changing the dynamic behavior of a carrier.

The invention discloses a strapdown inertial navigation attitude algorithm precision evaluation method. A polynomial coefficient is set according to a required carrier dynamic environment; according to the polynomial, calculating attitude truth values of all time needing reference in an off-line manner; deriving an angular velocity analytical expression according to the attitude truth value, and generating gyroscope observation; the method comprises the following steps: taking gyroscope observation as input of a strapdown inertial navigation attitude algorithm to be evaluated, updating attitude parameters of a carrier, and obtaining an attitude calculation result; after each attitude algorithm is solved, the algorithm performance is quantitatively evaluated; after each algorithm performance evaluation, adjusting parameters and a coefficient matrix of the attitude trajectory model or storing current evaluation data; and storing the adjusted model parameters or evaluation data, and when a new high-order attitude algorithm needs to be verified or a maneuvering scene needs to be further expanded, turning to the initial step and sequentially carrying out recursive iteration until an evaluation task is completed. According to the method, large-angle maneuvering scene simulation and attitude / angular velocity analysis truth value acquisition can be considered, and the high-order attitude algorithm performance can be verified more accurately and efficiently.

The application belongs to the field of dynamics, and specifically provides a method for comprehensively characterizing the performance and carrier dynamics of quantum dot light-emitting diodes (QLEDs) under low-temperature conditions. The method includes variable-temperature efficiency testing, variable-temperature transient electroluminescence testing, variable-temperature electric-pumping transient absorption testing, and variable-temperature transient current testing, which can independently characterize the electron and hole dynamics of QLED devices at different temperatures to systematically analyze the influence of low-temperature environments on the processes of carrier injection, transport, accumulation, and recombination. Through this characterization method, the influence of low temperature on the performance of QLEDs can be accurately evaluated, helping to optimize device design and improve the stability and working efficiency of QLEDs in extreme environments, thereby promoting the practical application of QLEDs in the fields of display and lighting.

A kind of material measuring system and method of coaxial degenerate and non-degenerate type ultrafast carrier dynamics, the system is compatible with coaxial degenerate and non-degenerate type pumping probe light path;Resonance process and different energy level interaction process of material at single wavelength are observed, and detection sensitivity and selectivity are improved.The system uses microscopic objective imaging and utilizes three-dimensional high-precision electric displacement table to adjust the position of sample to be measured, and can realize real-time monitoring of the surface morphology of micron-sized sample and light spot;The system uses photoelectric detector to synchronously test sample transmission and reflection signals, solves the problem that it is difficult to completely and accurately measure the ultrafast carrier dynamics process of micro-area different types and different thickness materials.Optimize ultrafast carrier dynamics process measurement technology and expand its applicable range.The application realizes automatic control, with the technical characteristics of quick, sensitive and high integration.

The invention discloses a scanning imaging system based on an exciton resonance absorption principle. The system is composed of a semiconductor sample with exciton resonance absorption characteristics, an excitation light source, a mechanical chopper, an optical microscopic system, a displacement table, a photoelectric detector, a lock-in amplifier and a computer. The excitation light source provides narrow-band light with a specific central wavelength, the narrow-band light is irradiated to a semiconductor material sample with an exciton resonance absorption characteristic through the optical microscopic system or the lens group, and the position of the narrow-band light excitation sample is controlled through the displacement table. The narrow-band light reflected or transmitted by the semiconductor material is incident on the photoelectric detector through the optical microscopic system, and the computer processes the obtained electric signal to obtain a carrier distribution two-dimensional image in the surface of the semiconductor sample. The method has the characteristics and advantages of simple system structure, low cost and carrier dynamics visualization.

The present application relates to a kind of near-field optical super-resolution carrier dynamics imaging system, wherein probe light is shot into near-field optical scanning microscope system by probe beam expander component and probe attenuator component, pump light is sequentially shot into near-field optical scanning microscope system by pump beam expander component, pump attenuator component, pump light delay component and acoustooptic modulator component, near-field optical scanning microscope system includes upper objective lens, scanning probe, sample support, lower objective lens, near-field beam splitter, near-field filter component and convex lens in the direction of probe light path in turn, pump light is focused on sample after being reflected by near-field beam splitter and forming the path direction opposite to probe light and being shot into lower objective lens, probe light is shot out by convex lens and input into lock-in amplifier by fiber coupler and photomultiplier tube.The present application combines near-field optical super-resolution imaging technology with femtosecond transient absorption spectroscopy technology, and realizes the high space-time resolution visual detection of microcosmic carrier dynamics.

The present application relates to a kind of short-circuit current imaging, open-circuit voltage imaging, time-resolved fluorescence imaging and femtosecond transient absorption imaging combined perovskite solar cell comprehensive performance detection method and system.The method can obtain the photoelectric performance, carrier dynamics and interface characteristics of perovskite solar cell in real time by integrating four kinds of advanced imaging techniques.Short-circuit current imaging is used to measure the local photoelectric response of the battery under short-circuit condition, and open-circuit voltage imaging provides the potential distribution information of the battery surface, and time-resolved fluorescence imaging combined with femtosecond transient absorption imaging can monitor the dynamic process of carrier from picosecond to sub-millisecond.This comprehensive detection method provides multi-dimensional information for in-depth understanding of the performance and defects of perovskite material, and promotes the research and commercial application of perovskite solar cell.In summary, the present application provides an efficient and comprehensive detection scheme, and has important theoretical value and practical application prospect.

The application provides a polarization tailing error estimation method based on meta-learning in a high dynamic environment, and belongs to the field of bionic polarization navigation, and comprises the following steps: a polarization angle error database caused by tailing interference under different rotating speeds is established; in an offline stage, a rotating speed related network and a rotating speed independent network are trained based on a meta-learning strategy, polarization angle errors are decoupled into rotating speed related features and rotating speed independent features; in an online stage, when performing linear motion, a polarization / inertial navigation correction dynamic model three-dimensional attitude error is used; in turning motion, the rotating speed related features are taken as states, the polarization angle inverted by a carrier dynamic model is taken as a measurement, the rotating speed independent features are taken as a measurement matrix, the rotating speed related features are estimated, the rotating speed related features and the rotating speed independent features are fused, and the estimation of the polarization tailing error is completed. The application combines offline and online learning to complete adaptive estimation and compensation of the polarization tailing error under different rotating speeds in a high dynamic environment, and improves the navigation performance of a bionic polarization integrated navigation system.

The perovskite avalanche X-ray detector comprises a first electrode, a metal oxide layer, a perovskite thin film layer and a second electrode which are stacked in sequence. The high-density metal oxide thin film and the polycrystalline perovskite thin film form a heterojunction, a strong electric field of a heterojunction interface induces carrier avalanche multiplication under reverse bias, signal current amplification is achieved, the detection performance is remarkably improved, and the blank of the detector is filled for the first time. According to the scheme, the metal oxide and the perovskite are selected to construct the heterojunction, the characteristics and the carrier dynamics process are regulated and controlled, and the sensitivity is improved. The traditional structure is broken through, the magnetron sputtering and solution method processes are mature and controllable, and large-area preparation is easy. Under the bias voltage of-20 V, the sensitivity of the device is improved by more than 16 times, the gain is adjustable along with the bias voltage, the process repeatability is high, and the device is suitable for the field of high-sensitivity X-ray detection.

The application discloses a design method of a distributed feedback laser and related devices, applied to the field of optoelectronic technology, comprising: obtaining first structure parameters of the laser; applying random disturbance to the initial reflection phase of the high-reflection coating end, and statistically obtaining multiple sets of second structure parameters and corresponding parameter indexes under each disturbance according to the first structure parameters; determining a robust window of the second structure parameters according to a preset standard and the parameter indexes; statistically obtaining multiple sets of coupling coefficient ratios and corresponding parameter indexes within the robust window of the second structure parameters; and determining optimal structure parameters of the laser with the optimal parameter index as the target. For an asymmetric distributed feedback laser with a first grating section and a second grating section, the longitudinal spatial hole burning effect is described by an optical field weighted carrier dynamics parameter, and the longitudinal spatial hole burning effect of the distributed feedback laser can be effectively reduced after optimization based on the optical field weighted carrier dynamics parameter.

The application relates to a low-threshold plasmonic graphene all-optical nonlinear activator, which comprises a substrate, a gold film is covered on the substrate, a device pattern is etched on the gold film, and a graphene film is covered on the gold film. The gold film pattern of the plasmonic structure can generate a very strong local field enhancement effect, significantly enhancing the interaction between light and graphene; by utilizing the Pauli blocking effect and the ultrafast carrier dynamics of graphene, combining the local field enhancement effect of the plasmonic structure to strengthen the light-matter interaction, low-threshold nonlinear activation is realized. The device activation threshold is as low as 7.03 nW, and the accuracy in MNIST handwritten digit recognition is 96.7%; by eliminating the photoelectric conversion link, a low-power-consumption, high-energy-efficiency optical domain processing scheme is provided, and the practicability of optical neural network calculation is significantly improved.