In this paper, the finite element model of the fiber optic plates is established by using the finite element software. The simulation process is basically in line with the actual production process of the fiber optic plates. According to the simulation results, the deformation degree and speed of each part of the fiber optic plates in the process of melting pressure, as well as the changes of stress and strain of each part in the process of forming are analyzed. The results show that the deformation speed and degree of different parts are different in the process of melting pressure of fiber optic plates, especially the upper and lower end faces and side edges of fiber optic plates; and the stress and strain of each part are constantly changing, and the stress and strain values of the upper and lower end faces and side edges of fiber optic plates are larger than others.
Microchannel plate (MCP) is an important compact two-dimension multiplier for parallel multiplication of charged particles. With the advantages of high temporal resolution, high spatial resolution, high electron gain and compact structure, microchannel plate has become an important potential readout device for cryogenic quantum computing, such as the quantum computation based on floating electrons of liquid helium surface. For the sake of ultra-fast reading, it requires the signal readout time is less than 10-5 s at a temperature lower than 30K in the cryogenic quantum computing. However, the bulk resistance of MCP multiplier became giant at cryogenic temperature for the property of huge negative temperature coefficient of resistance, almost 105 Gohm at 20K~30K, resulting in a readout time of 10-2 -1s at cryogenic temperature, which was one of the major bottlenecks for the application of MCPs in the cryogenic quantum computing. In this paper, the bulk resistance of MCPs in two different bismuth contents (1at%, 2.4at%) under the same hydrogen reduction temperatures (730K) were present as the surrounding temperature controlled from 300K to 20K. The cryogenic bulk resistance of MCP was only decreased into 24% with the increase bismuth content from 1at% to 2.4at%, while thereof the normal bulk resistance was decline into 5%. The normal bulk resistance reduced only in the manner of improving the conductivity of conductive layer, could also increase the temperature-resistance sensitivity of MCP, leading an even greater temperature coefficient of resistance, which deteriorated the stability of readout in the cryogenic quantum computing.
Microchannel plate (MCP) is an important compact signal multiplier. The dynamic range of MCP is the key index influencing the detection quality of high flux, high energy and wide output linearity signals, but limited on the bulk resistance of MCP multiplier. Therefore, the problem of the bulk resistance-dependent of dynamic range transition in these devices needs to further continues to be investigated. In this paper, lead silicate glass microchannel plates in three different bismuth contents (0at%, 1at%, 2at%) were present. The bulk resistance decreased exponentially (from 6000MΩ into 15MΩ) with the increase of the content of bismuth in the lead silicate glass from 0at% to 2at%, meanwhile, the dynamic range was increased from 3.3×102 to 2.3×103 . As the bulk resistance of MCP multipliers dropped from 150MΩ into 15 MΩ (dropped about 90%), while the dynamic range of that just extended by seven times, meanwhile, the dark current of that boosted almost ten times (from 1pA to 10pA). It implicated that the dynamic range of MCP multiplier was influenced not only by the charge replenishment abilities involved in the bulk resistance, but also by the joule heating effect-depended dark current variation concerned with the bulk resistance.
The R2O-SiO2-B2O3 glass has emerged as an important material due to its high performance. Annealing condition has significant effect on the properties of R2O-SiO2-B2O3 glass. R2O-SiO2-B2O3 glass has been annealed in different temperature and holding time. The influence of the annealing condition on the properties of R2O-SiO2-B2O3 glass such as hardness, refractive index, and transmissivity were systematically studied. The results indicate that the annealing process can reduce glass hardness and improve refractive index significantly, but enhance transmissivity slightly. The optimal performance of the R2O-SiO2-B2O3 glass can be obtained under the annealing temperature of 650°C with the holding time of 4h.
The R2O-SiO2-B2O3 glass has emerged as an important material due to its high performance. During the process of glass melting, copious amounts of bubbles can be produced. The bubbles are considered as serious defects of the R2O-SiO2-B2O3 glass and can induce negative effects on properties of glass, such as optical uniformity, mechanical property, etc. The influence of the fining agents on the properties of R2O-SiO2-B2O3 glass such as density, refractive index, and transmissivity were systematically studied. The results indicate that fining agents had influence on the density of the R2O-SiO2-B2O3 glass, fining agents do not have obvious impact on the refractive index and transmissivity of R2O-SiO2-B2O3 glass.
In this paper, the properties of transition metal oxide borate glass were studied. It was found that introducing a small amount of CaO and BaO into borate glass could improve the crystal resistance and chemical stability of the glass. The introduction of V2O5, ZnO, Al2O3, SiO2 and other components is beneficial to widen the glass forming range and improve the anti-crystal performance of glass. The introduction of MgO and ZrO2 can improve the acid resistance of glass. The mixed and co-mixing of Fe2O3, MnO2, V2O5 and other transition metal oxides can increase the total doping amount by more than 30%. At the same time, the introduction of multiple components can effectively prevent glass crystallization and improve the anti-crystallization ability. The developed transition metal oxide borate glass has a resistivity up to 5×1010•cm, good chemical stability and anti-crystallization ability, and is suitable for the production of large crucible melting, realizing the preparation of 100×100×1mm glass samples.
Cracks in microchannel plate (MCP) seriously reduce the mechanical and electrical properties of MCP. The generation mechanism of cracks and the structure of sub-surface damage layer were revealed by studying the changes of surface morphology of MCP in optical process and chemical treatment process. The source of cracks appeared in the etching and reduction process is the sub-surface damage layer in the optical process. The damage layer includes cracks and non-uniform strain layer. After slicing, the depth of damage layer visible to optical microscope is within 25μm. During the polishing process, the damage layer is deeper, and there is a non-uniform strain layer with the depth of about 20μm. To avoid the occurrence of cracks, the thickness setting in the slicing process should take into account the slice damage layer, the polishing crack growth layer, and the strain layer.
The resistive plate chamber (RPC) is a gaseous parallel-plate detector, the glass resistive plate is the key element of RPC. In order to meet the requirement of high flux particle detection, it is urgent to develop low resistivity electroconductive glass. For this purpose, we designed the glass of SiO2-B2O3-P2O5-Al2O3-MxOysystem, the MxOy was chosen as Fe2O3, V2O5 and MnO2. In this paper, the formation abilities and conductive properties of glass were studied by adjusting the contents of the glass forming body and MxOy. The results showed that P2O5-Al2O3and P2O5-B2O3 built a quasi-[SiO4] tetrahedron structure as the glass forming body, the SiO2strengthened the network, which greatly improved the stability of the glass. Meanwhile, the addition of B2O3 and P2O5 could enhance the doping ability of MxOy in the whole glass system, which was benefit to reduce the resistivity of glass. Three transition metal oxides were added to the same base glass, and their resistivity was in order: ρFe＜ρV＜ρMn. The relationships between the oxidation-reduction atmosphere of glass melting and the resistivity of glass were investigated. The conductivity types was confirmed to be electronic conductive by testing the Seebeck coefficient and Hall effect of glass. The resistivity of the developed SiO2- B2O3-P2O5-Al2O3-Fe2O3 electronic conductive glass system was reached to1010Ω·cmlevel.
Resistive Plate Chambers are planar, gaseous detectors made with electrodes and resistive plates, which is divided into single-gap (RPC) and multi-gap (MRPC). Such detectors have a simple structure, good time resolution, high efficiency, small dead zone, flexible signal readout mode and a relatively low cost, etc. Therefore, it has extensive and important applications in high energy physics, nuclear physics and other fields. The resistive glass plate has good stability and is less affected by the environments, which ensures the uniformity of the electric field inside the detector and makes the detector have lower dark current and noise. In this paper, the influence mechanism of resistive glass on detector performance was introduced firstly. Then the application and research status at home and abroad were summarized. On this basis, the existing problems in the research of resistive glass were expounded. Finally, according to the application requirements of RPC under the condition of high particle fluxes, the future development trend was analyzed and proposed. The author believes that it is the future development trend and direction in the field of resistive glass to carry out research on high-performance resistive glass materials and develop pure electronic conduction glass materials with volume resistivity of 109Ω•cm ~1010Ω•cm through composition design and control. At the same time, in order to meet the manufacturing requirements of large area array detectors, the strength, chemical stability and the possibility of batch manufacturing of the glass should also be fully considered in the development process of resistive glass.