2118 results about "Molecular physics" patented technology

The invention discloses a process and a device for continuously synthesizing vitamin D3 through photocatalysis, and relates to the technical field of process on-line monitoring and intelligent control. Photochemical reaction requirements under raw materials with different concentrations are matched through multi-band illumination weight dynamic distribution; when the concentration of the 7-dehydrocholesterol fluctuates, the illumination ratio of 290nm to 305nm wavebands is adjusted in real time by a reinforcement learning algorithm, so that the conversion of a pre-vitamin D3 intermediate is more efficient, and the competitive consumption of a by-product path is reduced; the reaction retention time is further optimized through synchronous flow rate adjustment, and local excessive irradiation caused by sudden concentration increase is avoided; the environment temperature and humidity change is incorporated into a state vector, and the control module generates a compensation instruction accordingly; and if the humidity changes suddenly, pulse type flow compensation is triggered to counteract reaction efficiency attenuation. A closed-loop response mechanism reduces the dependence on physical temperature control equipment, and is especially suitable for mobile production scenes.

The invention relates to the technical field of quantum computing and molecular electronic devices, in particular to a probabilistic bit device based on polyfluoroaryl methyl free radicals and a preparation method of the probabilistic bit device. According to the probabilistic bit device, the coupling efficiency of molecules and electrodes is improved by virtue of the characteristic that the paramagnetic unpaired electron spin state of tri (polyfluoroaryl) methyl free radical molecules can be used as a random expansion physical entropy source and high electronegativity and stability formed by modification of a plurality of strong electron-withdrawing fluorine atoms in the molecules. During the operation period of the device, the spin fluctuation can efficiently regulate and control tunneling current passing through molecules, promote random conversion between output high and low current states, show excellent random binary fluctuation characteristics, and simultaneously have high sensitivity and long coherence time. Compared with the prior art, the device has remarkable advantages in the aspects of device stability, energy efficiency ratio and external field controllability. The preparation method is simple and convenient to operate, mild in reaction condition and beneficial to large-scale production.

The invention discloses a high-reliability PbS quantum dot film, a preparation method thereof and a photoelectric device. The preparation method comprises the following steps: 1) obtaining a first quantum dot solution; 2) adding medium-chain and long-chain amine; 3) adding an anti-solvent; 4) obtaining medium-chain and long-chain amine modified PbS quantum dot solids; 5) obtaining a second quantum dot solution; (6) forming a PbS quantum dot coating; 7) forming a mercaptan solution; 8) coating the PbS quantum dot coating with a mercaptan solution; (9) annealing treatment; 10) forming a new PbS quantum dot coating, and coating the new PbS quantum dot coating with a mercaptan solution; according to the PbS quantum dot thin film and the preparation method thereof, through the induction and synergistic effect of halogen atoms, the binding capacity of halogenated mercaptan ligands and the surface of the PbS quantum dot thin film is enhanced, the surface defect state of the PbS quantum dots is effectively inhibited, and the reliability of the PbS quantum dot thin film and a photoelectric device under the conditions of high temperature, high humidity and long-time illumination is remarkably improved.

The invention relates to an organic molecule for the application in optoelectronic devices. According to the invention, the organic molecule hasa first chemical moiety with a structure of Formula I:anda second chemical moiety with a structure of Formula II:wherein W is the binding site of a single bond linking the first chemical moiety to the second chemical moiety,L is selected from a direct bond and a linking group with a structure of Formula BN-I:wherein the dashed lines denote the binding sites as indicated in Formula I, and # represents the binding site of the first chemical moiety to the second chemical moiety.

The invention provides a perovskite solar cell, a preparation method thereof and a photovoltaic module. The perovskite solar cell comprises a first electrode, a hole transport layer, a perovskite layer, an electron transport layer and a second electrode which are stacked in sequence. The material of the hole transport layer comprises a biomolecular material which is fixed on a self-assembly monomolecular layer material through an intermolecular force, and the biomolecular material comprises one or more of guanine, adenine, thymine, uracil, cytosine, hydroxymethylcytosine, xanthine, hypoxanthine, 6-mercaptopurine and corrin. According to the perovskite cell provided by the invention, the biomolecular material with a plurality of nitrogen heterocyclic structures and amino groups is added to generate multipoint hydrogen-bond interaction and pi-pi accumulation with the tail end of the SAM, so that the orderliness of molecular arrangement is improved, and the dipole direction and strength of the whole interface are regulated and controlled; and a coordination bond or hydrogen bond network is formed by the coordination compound and uncoordinated cations or anions in perovskite, so that interface defects are effectively passivated, and the thermal stability and the humid and hot life of a device are enhanced.

The invention belongs to the technical field of back contact cells, and particularly relates to a back contact cell with a specific front surface structure and a cell assembly thereof, and the specific front surface structure comprises a tunneling oxide layer and a specific doped amorphous silicon layer which are sequentially arranged on the front surface of a silicon substrate, a low-doped amorphous silicon layer, a high-doped amorphous silicon layer and an oxygen-doped amorphous silicon layer are sequentially arranged in the specific doped amorphous silicon layer along the direction far away from the tunneling oxide layer, and the specific doped amorphous silicon layer is doped with a P element and contains an H element; the P doping concentration C1 of the low-doping amorphous silicon layer and the P doping concentration C3 of the oxygen-doping amorphous silicon layer are respectively smaller than the P doping concentration C2 of the high-doping amorphous silicon layer, and the specific front structure enables the back contact cell to absorb incident light within 400 nm, and the highest absorptivity exceeds 85%. The back contact battery disclosed by the invention can still keep good performance after being exposed to ultraviolet rays for a long time, the UV reliability of the battery is improved, meanwhile, high light transmittance is realized, and relatively high battery efficiency is also realized.

The invention provides a method for detecting an external vesicle marker through high-flux nano plasma exciting light immune color development, and belongs to the technical field of human extracellular vesicles. After a serum sample is subjected to centrifugal treatment, the serum sample and a CD81 capture antibody substrate are incubated, and the particle size distribution of the vesicles is monitored in real time; a zwitterionic polymer modified gold nanoparticle LAM detection probe and a polyethylene glycol modified silver nanoparticle LprG detection probe are prepared to be specifically combined with a vesicle surface antigen, a chromogenic enhancement solution is adopted to induce a plasma resonance signal, and full-hole scanning imaging is carried out; and constructing a double-layer game optimization model to cooperatively optimize the detection sensitivity and the signal stability, carrying out weighted summation on normalized signals of the particle size subgroups to obtain comprehensive detection signal intensity, comparing the comprehensive detection signal intensity with a threshold value, and outputting a final judgment result. The technical problem that quantitative accuracy is affected by signal intensity deviation caused by vesicle particle size difference in outer vesicle marker detection is solved.

The invention belongs to the technical field of liquid crystal display, and discloses a multi-gray-scale cholesteric liquid crystal display device and a driving method thereof, according to the multi-gray-scale cholesteric liquid crystal display device and the driving method thereof, cholesterol liquid crystal of a pixel unit is controlled to be in a P state, an FC state and an intermediate stable state between the P state and the FC state through driving voltage, and the liquid crystal display effect is improved. And gray scale display of the pixel unit is realized. The driving time sequence of the bistable cholesterol liquid crystal is optimized, the proper driving voltage is selected, the cholesterol liquid crystal is controlled to be in an intermediate stable state through the driving voltage, and the display state of the cholesterol liquid crystal between the full-transmission state and the full-reflection state is increased, so that the gray scale number of the cholesteric phase display device is greatly increased on the premise that the number of sub-pixels is not increased, and the display effect of the cholesteric phase display device is improved. The display effect is improved.

A method and an apparatus for conformal boron doping of a three-dimensional structure. The method comprises: removing an oxide layer from a surface of a silicon-based three-dimensional (3D) substrate; forming, after removing the oxide layer, a first group of stacked films on a surface of the silicon-based three-dimensional substrate; forming a second group of stacked films on a surface of the first group of stacked films away from the silicon-based 3D substrate; depositing an aluminum oxide passivation layer on a surface of the second group of stacked films away from the first group of stacked films; and boron-doping the silicon-based 3D substrate through laser annealing or rapid thermal annealing, where the laser annealing or the rapid thermal annealing drives boron dopants, which comprises boron oxide, into the silicon-based 3D substrate via an auxiliary layer.

The invention relates to a UCNPs probe-based in-situ dynamic monitoring molecular interaction method, which comprises: S1, providing a UCNPs probe, the core layer of the UCNPs probe being a rare earth up-conversion nanocrystal, the shell layer of the UCNPs probe being an anti-quenching inert material, and the anti-quenching inert material coating the surface of the rare earth up-conversion nanocrystal; the surface of the anti-quenching inert material is modified with ligand molecules, and the ligand molecules are used for being specifically combined with target molecules in a to-be-detected sample; s2, mixing or contacting the UCNPs probe with a to-be-detected sample containing target molecules to construct a to-be-analyzed molecular interaction system; s3, irradiating the molecular interaction system by adopting near-infrared pulse laser, and collecting the change of the fluorescence lifetime tau of the UCNPs along with the time t and the change of the fluorescence intensity I along with the time t in real time to obtain a tau-t curve and an I-t curve; and S4, according to the tau-t curve and the I-t curve, realizing in-situ dynamic monitoring on the molecular interaction state. According to the method, a molecular binding / dissociation event is directly converted into a quantifiable and anti-interference optical signal, and the technical defect that in-situ dynamic monitoring of molecular interaction cannot be achieved in a traditional technology is overcome.

The invention provides a semiconductor epitaxial growth parameter inversion method, a semiconductor epitaxial growth parameter inversion system, a semiconductor epitaxial growth parameter detection device and a related product, and relates to the technical field of semiconductor detection. The gas phase transmittance of a detection light path is further obtained, quantitative compensation is carried out on the actually measured reflection spectrum in the semiconductor epitaxial growth process, the compensated target reflection spectrum is closer to the real optical response of a semiconductor epitaxial film, and therefore spectral shape distortion and system errors caused by gas phase absorption superposition are effectively weakened. And the accuracy and the stability of the inverted growth parameters are obviously improved. Furthermore, the quantitative compensation value can be adaptively updated according to the fluctuation of the working condition, the inversion deviation introduced by the drift of the working condition is reduced, the consistency and comparability of the process are improved, and more reliable end point control and parameter closed-loop optimization can be conveniently realized.

This application relates to a monolithically integrated multi-wavelength topological cavity surface-emitting laser (PCSEL) array. According to one embodiment, a monolithically integrated PCSEL array includes multiple PCSELs formed from the same semiconductor layer, at least one layer of which is formed as a photonic crystal layer, or the laser also includes a separate photonic crystal layer. The photonic crystal layer includes multiple supercell structures, each with substructures having multiple independent one-dimensional parameters. At least two independent one-dimensional parameters of one or more substructures are modulated to be greater than or less than their equilibrium position to open the Dirac point of the supercell's bandgap at the equilibrium position. Around any point in the photonic crystal layer, the modulation of the two independent one-dimensional parameters of the supercell forms a vortex structure, which corresponds in parameter space to one or more turns around the equilibrium position. The supercell lattice constants of the two lasers can be different to emit lasers of different wavelengths.

The invention provides a method for analyzing femtosecond laser-induced damage behaviors on the surface of a Zn-doped KDP crystal, and belongs to the technical field of engineering optics based on computer data processing. The method comprises the following steps: firstly, respectively analyzing the influence of the Zn doping amount on the band gap and electroacoustic coupling of the KDP crystal through an ultraviolet-visible absorption spectrum and a Brillouin light scattering spectrum; then constructing a one-dimensional model, respectively simulating the electron density, lattice temperature and time evolution of electron temperature on the surface of the Zn-doped KDP crystal under femtosecond laser irradiation through an electron density accumulation rate equation and a double-temperature model, and theoretically analyzing the influence of the Zn doping amount on the damage behavior of the surface of the KDP crystal. And a theoretical model for calculating the femtosecond laser induced damage threshold is established, so that the optimal doping amount of Zn is determined in a lossless manner. A real sample is not contacted, so that the sample utilization rate is improved; the simulation process is more stable and controllable, and the data repeatability is high; and the research period can be shortened, and optimal doping amount screening is accelerated.

The invention provides a laser crystal heterogeneous bonding method and an optical element, and relates to the technical field of laser, and the method comprises the steps: carrying out the ultra-precise surface treatment of the to-be-bonded surfaces of a laser crystal and a heterogeneous material based on the laser crystal and the heterogeneous material; respectively depositing at least one transition layer on the two to-be-bonded surfaces after surface treatment through a physical or chemical deposition method; the outermost layers of the two transition layers are made of the same material; carrying out ion beam activation treatment on the two surfaces to be bonded on which the transition layers are deposited so as to form high-activity surfaces; and aligning the two activated surfaces to be bonded in a vacuum environment at room temperature and applying pressure, and realizing room-temperature bonding through electrostatic force and chemical bond action to obtain a bonding body of the laser crystal and the heterogeneous material. According to the invention, thermal-mechanical property and chemical property differences among heterogeneous materials are overcome, and high-strength, low-stress and high-optical-quality bonding is realized.

A crystal pulling method and system for fabricating a large-diameter silicon single crystal, and a silicon single crystal and a medium. The method can comprise: performing global two-dimensional simulation on a crystal pulling process, and acquiring a global temperature distribution, a velocity field distribution and an initial solid-liquid interface value during the crystal pulling process under a preset crystal pulling apparatus and a preset crystal pulling parameter; on the basis of the global temperature distribution and the velocity field distribution, determining a boundary condition, and on the basis of the boundary condition, performing local three-dimensional simulation on the crystal pulling process to determine a target solid-liquid interface value; adjusting the preset crystal pulling parameter until the initial solid-liquid interface value is equal to the target solid-liquid interface value within a threshold range, and using the adjusted preset crystal pulling parameter as a reference crystal pulling parameter; on the basis of the reference crystal pulling parameter, simulating and calculating a simulated defect during the crystal pulling process; on the basis of the simulated defect, iteratively optimizing the reference crystal pulling parameter until the simulated defect meets a preset condition, and using the optimized reference crystal pulling parameter as a target crystal pulling parameter; and fabricating a defect-free silicon single crystal.

The invention relates to the technical field of photoinitiators, and provides a triplet-triplet energy transfer (TTET) free radical I type photoinitiation system, a photocuring composition and application thereof. The system comprises a boron dialkylated dipyrromethene free radical I type photoinitiator and a long wave absorption photosensitizer, the photosensitizer is preferably an osmium (II) complex, and the mass ratio of the photosensitizer to the photoinitiator is preferably 1: 5-1: 200. Under the irradiation of a 650-750 nm light source (preferably a 690 nm LED), the photosensitizer enters a triplet state through intersystem crossing and generates TTET to the photoinitiator, so that the photoinitiator is uniformly split in the triplet state to generate free radicals, thereby initiating polymerization / cross-linking curing of monomers such as (methyl) acrylate and the like. The embodiment shows that the double bond conversion rate of the TPGDA can reach more than 80% within 10 minutes under the conditions of LED at 690 nm and 80 mW / cm < 2 >.

A long-persistent luminescence emitter containing a polymer that contains, relative to the total molar amount of an electron donor structural unit and an electron acceptor structural unit therein, 70 mol % or more of an electron donor structural unit and less than 30 mol % of an electron acceptor structural unit, or containing a polymer that contains, relative to the total molar amount of an electron donor structural unit and an electron acceptor structural unit therein. 70 mol % or more of an electron acceptor structural unit and less than 30 mol % of an electron donor structural unit. The emission decay after stopping light irradiation to the emitter is power law decay.

The invention relates to the technical field of optical elements, in particular to a structural color regulation and control device based on silicon nitride metasurface continuous domain bound state enhancement, which comprises a substrate and a metasurface structure arranged on the substrate, the substrate is a silicon dioxide substrate, and the metasurface structure is composed of a plurality of nano-disks which are periodically arranged in a two-dimensional manner. And a circular air hole is formed in the nano plate. Based on the narrow linewidth resonance characteristic of the quasi-BIC, the structural color with high saturation and wide color gamut is realized; by utilizing strong polarization dependence, passive and dynamic regulation and control of color brightness can be realized through simple polarization rotation, and the structure does not need to be changed; silicon nitride has extremely low loss in a visible light band, good compatibility with a silicon dioxide substrate and a stable structure; a high-contrast polarization encryption pattern is easy to realize, and the application prospect in the fields of high-end anti-counterfeiting, information storage, dynamic display and the like is wide; the adopted micro-nano processing technology is standard and mature, and practical preparation and industrialization of the device are facilitated.

According to the deep ultraviolet laser epitaxial structure and the epitaxial growth method thereof provided by the invention, the Al component of the first waveguide layer is linearly and progressively increased from the side close to the electron injection layer to the side close to the quantum well active layer; or the Al component of the second waveguide layer is linearly and progressively decreased from the side close to the quantum well active layer to the side close to the hole injection layer to form refractive index distribution which takes the barrier layer of the quantum well active layer as the highest refractive index point and gradually decreases towards one side (the n-type side or the p-type side), so that the light field is firmly bound near the quantum well active layer, and the light limiting capability is remarkably enhanced; meanwhile, high-low Al components of the p-type side (the second waveguide layer) gradually change to generate a strong polarization electric field, ionization of a p-type doped acceptor (such as Mg) can be promoted, two-dimensional hole gas (2DHG) can be induced, and the hole concentration is improved; the low-high Al components of the n-type side (the first waveguide layer) are gradually changed, so that two-dimensional electron gas can be induced, and the electron concentration is improved.

The invention relates to a solar cell and a preparation method thereof, the solar cell comprises a semiconductor substrate, a first polarity structure, a second polarity structure and a mixed passivation structure, and the semiconductor substrate comprises a first surface with a first region and a second region which are adjacently arranged; the first and second polar structures are respectively positioned in the first and second regions; the mixed passivation structure comprises a dielectric passivation layer which is located in the first region and comprises a first part covering the top surface of the first polar structure and a second part covering the side wall, close to the second polar structure, of the first polar structure; the intrinsic passivation layer comprises a third part located between the semiconductor substrate and the second polar structure and a fourth part located on the side wall, close to the first polar structure, of the second polar structure, and the fourth part and the second part are in contact overlapping in the direction perpendicular to the semiconductor substrate. According to the solar cell and the preparation method thereof, the problem of insufficient boundary passivation in a whole-surface amorphous silicon deposition process is avoided, and the device performance is improved.

The invention discloses a preparation method of a flexible infrared super-surface absorber based on MDM, and belongs to the field of micro-nano machining patterning. The method comprises the following steps: pretreating a polymer material; depositing a layer of bottom metal film on the pretreated substrate by adopting magnetron sputtering; a metal reflecting layer, a dielectric insulating layer and a metal surface functional layer are sequentially deposited through magnetron sputtering, a periodic nano microstructure is constructed on the surface of a flexible composite film, a nano round pit array is etched in situ on a surface metal layer of an MDM structure by using a femtosecond laser selective etching process, and an MDM laminated structure is formed. According to the invention, stable integration of the MDM structure and the flexible substrate can be realized, and meanwhile, high absorptivity and good flexibility of the device in an infrared band are ensured. The absorber prepared by the invention can generate resonance absorption on incident infrared electromagnetic waves through a surface plasmon and F-P cavity resonance coupling mechanism, and meanwhile, the characteristic size variation is changed through physical excitation, so that effective absorption and frequency regulation of the electromagnetic waves at the infrared band of 3-14 microns are realized.

The present invention belongs to the technical field of biology. Disclosed are a crystal form of a complement factor B inhibitor, a preparation method therefor and the use thereof. Specifically, the present invention provides a crystal form of a compound represented by formula I, a preparation method therefor and the use thereof. The crystal form prepared by the present invention has good stability, for example, crystal form stability and thermal stability.

Described herein are variations of a sensor configured to generate a signal that is indicative of a concentration of an analyte in a fluid. The sensor may include a working electrode comprising an electrode material, a biorecognition layer disposed at least partially on the electrode material and comprising a biorecognition element that selectively and reversibly binds to an analyte, and an at least partially desiccated hydrogel disposed on the biorecognition layer. In some variations, the biorecognition element may be functionalized with a redox-active molecule and is configured to change conformation upon binding the analyte to move the redox-active molecule, closer to, or further from, the electrode material. In some variations, the biorecognition element may be an aptamer.

The invention discloses a trans-perovskite solar cell and a preparation method thereof. The trans-perovskite solar cell comprises a conductive substrate, a hole transport layer, a passivation layer, a perovskite absorption layer, an electron transport layer and a back electrode layer which are arranged in sequence, the hole transport layer is made of nickel oxide; the passivation layer is made of cerium oxide, and the thickness of the passivation layer is 2-5nm; the light incidence direction of the solar cell is from one side of the conductive substrate to one side of the back electrode layer. Ce < 3 + > in cerium oxide is preferentially combined with dangling bonds on the surface of NiOx to form Ce-O-Ni bonds, so that interface defects are eliminated; the cerium oxide energy level is located between the perovskite and the hole transport layer, so that an energy level buffering effect is achieved, and the photoelectric conversion efficiency is improved; the Ce < 3 + > / Ce < 4 + > valence state conversion characteristic of cerium oxide can efficiently absorb and convert ultraviolet photons and prevent the ultraviolet photons from damaging a perovskite lattice structure; the fluorite structure of CeO gamma forms an ion diffusion barrier to block Ni < 2 + > from migrating to a perovskite layer and protect the perovskite structure.

The invention provides a method and a system for generating a multiphase powder X-ray diffraction crystal structure. The method comprises the following steps: acquiring a powder X-ray diffraction experiment spectrum; the powder X-ray diffraction experiment spectrum is input into a decoupling encoder, a plurality of crystal structure target potential factors output by the decoupling encoder are obtained, and the decoupling encoder is constructed based on independence loss among the crystal structure sample potential factors; and inputting the plurality of crystal structure target potential factors into a conditional diffusion model to obtain a target crystal structure corresponding to the powder X-ray diffraction experiment spectrum output by the conditional diffusion model, and the conditional diffusion model is obtained based on training of the crystal structure sample potential factors. According to the method, the crystal structure information can more purely and more accurately encode the core structure characteristics, and the success rate and the accuracy of analyzing the crystal structure from the complex atlas are remarkably improved, so that high precision and high robustness are obtained.

The invention belongs to the field of lasers, and discloses a growth method for reducing laser Ith through N grating burying, which subversively adopts an N-type grating structure, uses a built-in P-N junction formed by the N-type grating structure and a subsequent P-type buried layer as a natural and efficient current blocking layer, and structurally eliminates a current leakage path. Afterwards, in the heating stage, trace arsine is introduced to carry out atomic-scale protection on the sensitive grating morphology, at the optimal mass transport temperature, the high mobility characteristic of indium atoms is utilized to carry out shape-preserving filling on grating grooves, flawless preliminary planarization is achieved, and through variable-temperature thickening growth and high-temperature annealing in the pure phosphorus atmosphere, the high-temperature-resistant grating is obtained. And performing quality optimization and defect repair on the buried layer and the key interface. The series of linked steps ensure that the indium phosphide buried layer with flat atomic scale and complete crystal lattice can grow on the fragile N-type grating, and ensure that a high-quality covering layer and an active region grow on the N-type grating.

The invention discloses an explanation method for damage threshold improvement of a fused quartz material in a femtosecond laser processing / welding process. By establishing a fused quartz electron-lattice heat transfer model under femtosecond laser irradiation, a dissociation model of environment molecules and interstitial molecules under the action of femtosecond laser and a defect-containing fused quartz molecule dynamic reaction model based on a ReaxFF reaction force field, atomic structure changes in a system before and after a reaction are analyzed; and finally, obtaining a chemical reaction mechanism of the fused quartz containing the defects under the action of the femtosecond laser, and explaining the phenomenon that the damage threshold of the fused quartz is increased after the fused quartz is irradiated by the low-flux femtosecond laser. According to the method, the research in the current fused quartz femtosecond laser processing / welding process is perfected, and meanwhile, the theoretical blank that the damage threshold lifting mechanism is not clear in the fused quartz glass femtosecond laser processing / welding process is filled up.

The invention discloses iron oxide nanoparticles capable of responding to particle size change in a tumor microenvironment and a preparation method of the iron oxide nanoparticles, and belongs to the technical field of biomedical nano materials. The nano-particle comprises an iron oxide nano-crystal core with the particle size of 3-5nm and a tumor microenvironment response layer coating the surface of the iron oxide nano-crystal core. The response layer contains groups, such as disulfide bonds, enzyme digestion peptide fragments and the like, which can respond to acidic pH, high-concentration reduced glutathione or matrix metalloproteinase and other tumor characteristic stimuli to generate structural changes. In a tumor microenvironment, the hydration particle size of the nanoparticles can be directionally and controllably converted from 3-20 nm to 20-100 nm (or reversely). The preparation method mainly comprises two steps of preparing the core by a thermal decomposition method and modifying the surface response layer. The technical problems of insufficient tumor targeted enrichment capacity, limited imaging contrast and difficulty in balancing permeation and retention caused by fixed particle size of the existing iron oxide nanoparticles are solved, and the accuracy and efficiency of tumor diagnosis and treatment can be remarkably improved.

The invention provides a vertical cavity surface emitting laser and an epitaxial growth method thereof, and belongs to the technical field of semiconductors. The vertical cavity surface emitting laser comprises a substrate, an N-DBR, an active region growth layer, an oxidation limiting layer, a tunnel junction, a P-DBR and a surface ohmic contact layer which are stacked in sequence. The tunnel junction comprises a p + + layer, a first diffusion barrier layer, an n + + layer and a second diffusion barrier layer which are stacked in sequence. The p + + layer and the n + + layer are obtained through pulse doping growth, and P-DBR growth is carried out after stepped heating is carried out on the tunnel junction. The invention provides a comprehensive process based on pulse doping, an in-situ protection layer and stepped heating control, pulse doping is adopted when the n + + / p + + layer of the tunnel junction grows, the first diffusion barrier layer, the second diffusion barrier layer and the stepped heating process in subsequent growth are combined, and doping diffusion is remarkably inhibited while high conductivity of the tunnel junction is maintained.

The invention relates to the technical field of solid-liquid interfaces and liquid drop movement and control, in particular to a method and device for achieving left-right controllable spontaneous rotation of liquid drops based on light induction, and the method comprises the following steps that acid liquid drops containing photoacid are dropwise added to the surface of liquid metal; a light source system is adopted to irradiate liquid drops on one side of the liquid drops, the liquid drops are induced to locally release non-uniform H < + > ions, and interface chemistry is initiated to generate gradient change distribution; the light intensity generated by the light source system promotes the formation of asymmetric tension distribution on the liquid drop and liquid metal interface, and drives the liquid drop to rotate along a preset direction; and by changing the irradiation position, the liquid drops can be switched between left rotation and right rotation. According to the present invention, by using the mechanism of combining the interface Marangoni effect and the light-induced acidity regulation and control, the stable and rapid spinning behavior of the liquid drop can be represented by adjusting the position, the irradiation time and the irradiation intensity of the illumination region, and the rotation direction can be reversibly switched between the left rotation and the right rotation.