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We have developed a low-energy particle experiment that alternately measures ions and electrons in space. The ability to switch between ion and electron measurements is achieved by simply adding ultra-thin carbon foils and positive and negative outputs to a conventional top-hat electrostatic analyzer and a high-voltage power supply, respectively. The advantage of this experiment is that it can perform both ion and electron measurements using only one MCP-based detector for electrons, since it detects secondary electrons emitted from the carbon foils. For the SS520-3 sounding rocket program, we prepared two identical energy analyzers, one for ions and the other for electrons to demonstrate this technique. Laboratory tests confirmed that the performance of the two analyzers was comparable to that of conventional analyzers for ion and electrons. The SS520-3 rocket experiment in the high latitude auroral region yielded observations that captured typical features of ions and electrons, which were similar to previous observations. Graphical Abstract

Lead silicate glasses are fundamental materials to a microchannel plate (MCP), which is a two dimensional array of a microscopic channel charge particle multiplier. Hydrogen reduction is the core stage to determine the electrical conductivity of lead silicate glass MCP multipliers. The nanoscale morphologies and microscopic potential distributions of silicate glass at different reduction temperatures were investigated via atomic force microscope (AFM) and Kelvin force microscopy (KFM). We found that the bulk resistance of MCPs ballooned exponentially with the spacing of conducting islands. Moreover, bulk resistance and the spacing of conducting islands both have the BiDoseResp trend dependence on the hydrogen reduction temperature. Elements composition and valence states of lead silicate glass were characterized by X-ray photoelectron spectroscopy (XPS). The results indicated that the conducting island was an assemblage of the Pb atom originated from the reduction of Pb2+ and Pb4+. Thus, this showed the important influence of the hydrogen temperature and nanoscale morphological transformation on modulating the physical effects of MCPs, and opened up new possibilities to characterize the nanoscale electronic performance of multiphase silicate glass.

An improved theoretical model to calculate the focal spot properties of coherent synchrotron radiation (SR) soft X‐ray beams by combining and aligning two microchannel plates (MCPs) is presented. The diffraction patterns of the radiation behind the MCP system are simulated in the framework of the electrodynamical model of the radiation emission from two‐dimensional finite antenna arrays. Simulations show that this particular optical device focuses the soft X‐ray radiation in a circular central spot with a radius of ∼4 µm. The study points out that such MCP‐based devices may achieve micrometre and sub‐micrometre spot sizes as required by many applications in the soft X‐ray range. Finally, based on experimental and theoretical results of the radiation transmission by this MCP‐based device, a new method to characterize the spatial properties of brilliant SR sources is discussed. Transmission properties and diffraction patterns generated by synchrotron radiation at the exit of an assembled couple of microchannel plates (MCPs) are inivestigated. A theoretical model to simulate the patterns and properties of the soft X‐ray beam emerging from this couple of MCPs is presented and discussed.

The electron collection efficiency ( ) of the photomultiplier tube based on microchannel plates (MCP-PMT) is limited by the MCP open area fraction. Coating MCP with a high secondary yield material is supposed to be an effective approach to improve . Both typical and coated MCP-PMTs are developed. A relative measurement method is proposed to characterize the collection efficiency performance. Results show that the PMT based on the coated MCPs has a significant improvement on , a good gain uniformity and a high precise energy resolution.

The microchannel plate (MCP) is an electron multiplier with millions of micro through-holes that must withstand strong vibrations and enormous shocks in spaceborne detectors. To ensure the reliability and robustness of the MCP in space applications, we proposed an equivalent mechanical model of the MCP to investigate its mechanical properties, since the direct creation of the finite element model using the finite element method (FEM) is not feasible. Then, we developed a test system to verify the effectiveness of the equivalent mechanical model. The results show that the error of harmonic response analysis and the test result is less than 10 %, which is acceptable. Finally, we conducted parametric studies of the MCPs and obtained the equivalent mechanical model of the MCPs with different geometric parameters. This study will help researchers to optimize the MCP for aerospace-grade detectors.

AZO(ZnO/Al 2 O 3 ) conductive films were deposited in the microchannel of microchannel plate (MCP) by atomic layer deposition (ALD). The prepared films were characterized, including analysis of the thickness and composition uniformity of AZO films. The MCP bulk resistance was also measured, and the effect of annealing treatment on bulk resistance was investigated. The results suggest that the use of trimethylaluminum in the preparation of AZO composite film within the microchannel of MCP leads to corrosion of ZnO, resulting in non-uniformity in film thickness and incorrect composition of the film. The problem was resolved by increasing the pulse time of trimethylaluminum to 500 ms, resulting in the successful preparation of an AZO film with a uniform thickness and composition in the microchannel. After annealing, the bulk resistance of MCP increases while the variation of bulk resistance with voltage decreases. Specifically, the bulk resistance of the MCP having a ZnO/Al 2 O 3 ratio of 7/2 only experiences changes of the same order of magnitude (∼10 8 Ω) after undergoing a 60-minute annealing process in N 2 at 300 °C, thus satisfying the requirements of MCP.

The microchannel plate (MCP) is susceptible to the adsorption of substantial amounts of gas during its fabrication process. To mitigate this, a uniform electron source is essential for effective electron scrubbing and gas removal. Thermionic emission, a method of electron generation, can be employed to create the electron source. In this study, a flat spiral filament was designed and simulated using the CST Studio Suite electron simulation software to assess the cleaning performance of the electron gun. The impact of variations in electron gun parameters on the uniformity of the electron beam and current density was systematically analysed. The simulation results show that, with filament, grid, focusing sleeve, and anode voltages set to 200 V, 500 V, 250 V, and 300 V, respectively, a uniform electron beam with a diameter exceeding 30 mm can be achieved. In order to obtain the current density (5~50 nA/mm2) required for the MCP, the temperature of the filament should be 1800–2000 K through theoretical calculation. These findings offer valuable insights for designing a more efficient electron gun for MCP scrubbing.

To meet the application requirements of neutron detectors, a novel large-area microchannel plate photomultiplier tube with a gate function (G-MCP-PMT) was developed in this study. A kind of regular hexagonal mesh electrode as the gated electrode was designed to achieve excellent gating functions for target pulse signals. The photoelectron transmittances for different mesh electrode sizes and voltages were studied via numerical simulations. To increase the effective detection area of the photocathode, an electrostatic-focusing electrode was designed in the G-MCP-PMT. By optimizing the structure of the focusing electrode, an effective photocathode detection surface diameter of 80 mm was achieved based on commercially available MCPs with a diameter of 56 mm. By adjusting the channel diameter configurations of the dual MCPs, the output pulse peak and time response of the large-area G-MCP-PMT can be flexibly adjusted. The experimental results indicate that when the large-area G-MCP-PMT is operated at −2700 V, the gate establishment time is approximately 50 ns. The extinction ratio of the large-area G-MCP-PMT is higher than 3000:1, and the maximum linear output current is greater than 300 mA at 250 ns FWHM, meeting application needs in various fields such as white neutron detection and laser radar.

Integrating functional perovskites on an amorphous microchannel plate (MCP) glass faces challenges regarding the lack of ordered nucleation sites and stringent thermal budgets. Herein, we propose a surface energetics-based atomic layer deposition (ALD) strategy to achieve template-assisted oriented BaTiO3 growth via a (101)-oriented anatase TiO2 seed layer. Systematic investigation of the TiCl4/O3 process reveals a kinetic-to-thermodynamic transition at 300 °C, triggering a singular (101) preferred orientation. Combined DFT calculations and Wulff construction elucidate that this texture evolution is governed by a thermally activated surface energy minimization mechanism, driven by the intrinsic stability of the (101) facet. Crucially, the optimized seed layer acts as a multifunctional template: it not only transforms BaTiO3 growth from random polycrystalline morphology to a singular (100) orientation with suppressed bulk carbonate impurities but also ensures excellent conformality and uniformity throughout the high aspect ratio microchannels. This study clarifies the thermodynamic mechanism of oriented growth on amorphous substrates, providing a versatile surface engineering pathway for constructing high-performance MCP-based heterojunction devices.

As a key component of electron multiplier device, a microchannel plate (MCP) can be applied in many scientific fields. Pure aluminum oxide (Al 2 O 3 ) as secondary electron emission (SEE) layer were deposited in the pores of MCP via atomic layer deposition (ALD) to overcome problems such as high dark current and low lifetime which often occur on traditional MCP. In this paper, we systematically investigate the morphology, element distribution, and structure of samples by scanning electron microscopy (SEM) and energy disperse spectroscopy (EDS), respectively. Output current of different thickness of Al 2 O 3 was studied and an optimal thickness was found. Experimental tests show that the average gain of ALD-MCP was nearly five times better than that of traditional MCP, and the ALD-MCP showed better sensitivity and longer lifetime.