- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
[IEEE 2018 28th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV) - Greifswald, Germany (2018.9.23-2018.9.28)] 2018 28th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV) - Measurement of Surface Potential Distribution of Fluorinated Polyimide Film
摘要： Metal-Dielectric-Metal structure is widely applied in many pulsed power systems, such as electro-vacuum devices, high power microwave equipment and particle accelerators. This kind of composite insulation is suffered with high gradient electric field, which may result in phenomena of surface flashover across the dielectric. Corresponding surface charges and trap characteristics are important parameters, determining final flashover. This paper is focused on surface charges distribution (SCD) and trap measurement of fluorinated polyimide film, to investigate influences of fluorination on surface potential distribution. Additionally, the treatment methods of fluorination including fluorinated gas proportion and applied time have significant influences on SCD. The improvement of SCD can lead to flashover threshold improvement. These results are effective to illuminate theoretical mechanism of fluorination suppression and optimize the treatment process.
关键词： trap characteristics,polyimide film,surface potential distribution,surface fluorination
更新于2025-09-09 09:28:46
-
[IEEE 2018 International Conference on Diagnostics in Electrical Engineering (Diagnostika) - Pilsen, Czech Republic (2018.9.4-2018.9.7)] 2018 International Conference on Diagnostics in Electrical Engineering (Diagnostika) - Study on the trap properties of nano-ZnO modified polyimide based on surface potential decay method
摘要： The space environment will charge the surface of the spacecraft. Due to the low discharge ability of the dielectric material, it may cause the surface discharge of the spacecraft and affect the normal work of the spacecraft. Polyimide is a typical dielectric material on the spacecraft, this paper attempts to improve the surface discharge ability by modifying polyimide with nano-ZnO. The research method is based on the surface potential decay platform, which is an intuitive approach to evaluate the states of surface charging. The surface potential decay characteristics of pure polyimide and its modified samples are tested. The surface potential decay mechanism of the dielectric is analyzed by calculating the trap characteristics. Results show that the surface potential of ZnO modified polyimide has less decrement and rate of decay than that of the pure polyimide. The deep trap density of electron trap and hole trap density is less than that of pure polyimide, the shallow trap of pure polyimide is the lowest. The change of electron trap level is small, while the hole trap level increases.
关键词： polyimide,hole trap,ZnO,electron trap,Surface potential decay
更新于2025-09-04 15:30:14
-
Increasing the Electron Mobility of ZnO-Based Transparent Conductive Films Deposited by Open-Air Methods for Enhanced Sensing Performance
摘要： The development of open-air, high-throughput, low-cost thin film fabrication techniques has immense potential and interest in optoelectronics. However, the oxygen-rich atmosphere associated with such processes can have detrimental effects on the electrical properties of the deposited films. An example of this is found in materials based on ZnO, for which atmospheric processing results in low mobility values. This stems mainly from adsorbed oxygen species at the grain boundaries, which limit carrier transport. This paper describes the effect of a low-temperature UV treatment on the electrical properties of ZnO and aluminum doped zinc oxide (ZnO:Al) films deposited by Atmospheric Pressure Spatial Atomic Layer Deposition (AP-SALD). Thanks to the mild UV treatment, a significant decrease in the amount of oxygen traps at the grain boundaries has been observed. This results in a large improvement of the carrier mobility, up to 47 times for undoped ZnO and 16 times for ZnO:Al. The effect of temperature (RT to 220 °C) during the UV treatment on the conductivity of undoped ZnO and ZnO:Al films is discussed. The study of the time-dependent conductivity of ZnO and ZnO:Al films using tunneling emission based models provides a simple means for extracting the grain boundary trap density, a critical parameter in semiconductors that is usually not easy to estimate. We show that the high conductivity of the UV-treated films can be preserved when exposed to oxygen at high temperature thanks to a very thin alumina (Al2O3) barrier layer. Finally, we demonstrate that the effect of UV illumination of thin ZnO films deposited in oxidizing atmospheres can be used to design improved UV or oxygen sensors.
关键词： oxygen trap,electron mobility,spatial ALD,grain boundary,UV treatment
更新于2025-09-04 15:30:14
-
Physical nature of electrically detected magnetic resonance through spin dependent trap assisted tunneling in insulators
摘要： We show that electrically detected magnetic resonance (EDMR), through spin dependent trap assisted tunneling (SDTT) in amorphous SiC, exhibits approximately equal amplitudes at very high (8.5 T) and very low (0.013 T) magnetic fields at room temperature. This result strongly supports an SDTT/EDMR model in which spins at two nearby sites involved in a tunneling event are coupled for a finite time in circumstances somewhat analogous to spin pair coupling in the spin dependent recombination/EDMR model of Kaplan, Solomon, and Mott (KSM) [Kaplan, Solomon, and Mott, J. Phys. Lett. 39, 51 (1978)]. Since a comparable near zero magnetic field change in resistance is also observed in these samples, our results support the idea that this magnetoresistance response is also the result of a KSM-like mechanism involving SDTT. Additionally, we observe a large enhancement in SDTT/EDMR at high field (8.5 T) for temperatures below 50 K, which suggests the potential utility of SDTT in spin based quantum computation and other spintronic applications.
关键词： spin dependent trap assisted tunneling,electrically detected magnetic resonance,spintronics,amorphous SiC,magnetoresistance
更新于2025-09-04 15:30:14
-
in a hybrid trap
摘要： We report on the production of a 41K-87Rb dual-species Bose-Einstein condensate in a hybrid trap, consisting of a magnetic quadrupole and an optical dipole potential. After loading both atomic species in the trap, we cool down 87Rb first by magnetic and then by optical evaporation, while 41K is sympathetically cooled by elastic collisions with 87Rb. We eventually produce two-component condensates with more than 105 atoms and tunable species population imbalance. We observe the immiscibility of the quantum mixture by measuring the density profile of each species after releasing them from the trap.
关键词： Bose-Einstein condensate,immiscibility,hybrid trap,dual-species,sympathetic cooling
更新于2025-09-04 15:30:14
-
Are camera traps fit for purpose? A rigorous, reproducible and realistic test of camera trap performance
摘要： Camera traps are now widely used to produce the data that inform critical, large‐scale conservation strategies, but insufficient attention has been paid to evaluating or validating their performance. A realistic, reproducible and rigorous test of camera trap performance has been developed, using a real animal target moving in different directions and at different distances from sets of up to six cameras. The test clearly shows differences in performance between camera trap brands and models that affect whether they are fit for research purposes, and the effects on camera performance of the small differences in mounting height and angle that are likely to arise when camera traps are used in the field.
关键词： occupancy,capture‐recapture,validation,camera trap,fit for purpose,trail camera
更新于2025-09-04 15:30:14
-
High-Fidelity Single-Qubit Gates on Neutral Atoms in a Two-Dimensional Magic-Intensity Optical Dipole Trap Array
摘要： As a conventional approach, optical dipole trap (ODT) arrays with linear polarization have been widely used to assemble neutral-atom qubits for building a quantum computer. However, due to the inherent scalar differential light shifts (DLS) of qubit states induced by trapping fields, the microwave-driven gates acting on single qubits suffer from errors on the order of 10?3. Here, we construct a DLS compensated ODT array based upon a recently developed magic-intensity trapping technique. In such a magic-intensity optical dipole trap (MI-ODT) array, the detrimental effects of DLS are efficiently mitigated so that the performance of global microwave-driven Clifford gates is significantly improved. Experimentally, we achieve an average error of e4.7 (cid:2) 1.1T × 10?5 per global gate, which is characterized by randomized benchmarking in a 4 × 4 MI-ODT array. Moreover, we experimentally study the correlation between the coherence time and gate errors in a single MI-ODT with an optimum error per gate of e3.0 (cid:2) 0.7T × 10?5. Our demonstration shows that MI-ODT array is a versatile platform for building scalable quantum computers with neutral atoms.
关键词： quantum computing,microwave-driven gates,optical dipole trap,magic-intensity trapping,neutral-atom qubits
更新于2025-09-04 15:30:14
-
The Luminous mechanism of Eu <sup>2+</sup> and Dy <sup>3+</sup> co-doped long persistent luminous fiber
摘要： Fiber-forming polymer polyethylene terephthalate chips were blended with Eu2+ and Dy3+ co-doped SrAl2O4 (SAOED) to afford luminous fiber with long and persistent afterglow. A dynamical model was set up to study the afterglow process in order to correlate the afterglow characteristics with the trap levels of SAOED and luminous fiber. The results indicated that the illustration of initial afterglow for luminous fiber was obviously lower than that of SAOED, but its decay process was moderately slow and therefore longer than that of SAOED. Compared with SAOED, the thermo-luminescence peak of the fiber shifted to the higher temperature, and its intensity was lower than that of SAOED. With the time extension of delay time after excitation, the depth of trap level for luminous fiber in our studies did not show any significant change. The afterglow decay behavior can be best fit by using I ? I0/(1 + bt)2; the fitting showed that the afterglow decay process followed the second order dynamics.
关键词： preparation process,luminous fiber,trap level,mechanism,afterglow
更新于2025-09-04 15:30:14
-
A versatile dual-species Zeeman slower for caesium and ytterbium
摘要： We describe the design, construction, and operation of a versatile dual-species Zeeman slower for both Cs and Yb, which is easily adaptable for use with other alkali metals and alkaline earths. With the aid of analytic models and numerical simulation of decelerator action, we highlight several real-world problems affecting the performance of a slower and discuss effective solutions. To capture Yb into a magneto-optical trap (MOT), we use the broad 1S0 to 1P1 transition at 399 nm for the slower and the narrow 1S0 to 3P1 intercombination line at 556 nm for the MOT. The Cs MOT and slower both use the D2 line (62S1/2 to 62P3/2) at 852 nm. The slower can be switched between loading Yb or Cs in under 0.1 s. We demonstrate that within a few seconds the Zeeman slower loads more than 109 Yb atoms and 108 Cs atoms into their respective MOTs. These are ideal starting numbers for further experiments on ultracold mixtures and molecules.
关键词： caesium,Zeeman slower,dual-species,ytterbium,ultracold atoms,magneto-optical trap
更新于2025-09-04 15:30:14
-
The selfie trap: A novel camera trap design for accurate small mammal identification
摘要： Camera traps are a popular tool for monitoring wildlife though they can fail to capture enough morphological detail for accurate small mammal species identification. Camera trapping small mammals is often limited by the inability of camera models to: (i) record at close distances; and (ii) provide standardised photos. This study aims to provide a camera trapping method that captures standardised images of the faces of small mammals for accurate species identification, with further potential for individual identification. A novel camera trap design coined the ‘selfie trap’ was developed. The selfie trap is a camera contained within an enclosed PVC pipe with a modified lens that produces standardised close images of small mammal species including: Brown Antechinus (Antechinus stuartii), Bush Rat (Rattus fuscipes) and Sugar Glider (Petaurus breviceps). Individual identification was tested on the common arboreal Sugar Glider. Five individual Sugar Gliders were identified based on unique head stripe pelage. The selfie trap is an accurate camera trapping method for capturing detailed and standardised images of small mammal species. The design described may be useful for wildlife management as a reliable method for surveying small mammal species. However, intraspecies individual identification using the selfie trap requires further testing.
关键词： small mammal,selfie trap,camera trapping,individual identification
更新于2025-09-04 15:30:14