Electron source device for ultrafast electron diffraction and ultrafast electron microscope

Abstract

The invention relates to an electron source device for an ultrafast electron diffraction and ultrafast electron microscope. The electron source device comprises a low-power microwave signal source, a phase shifter, a solid amplifier, a klystron, an attenuator and a current circulator, wherein the first phase shifter, the solid amplifier and the klystron are sequentially arranged in the direction along microwave signals output by the low-power microwave signal source, the output end of the klystron is connected with the input end of the power distributor, megawatt level microwave signals output by the klystron are divided into two paths by the power distributor, the first path of microwave signals are input into a cavity 1.5 arranged at the front part of an electron gun sequentially through the first attenuator and the current circulator, and the second path of microwave signals are input into a single cavity arranged at the back part of the electron gun sequentially through the second attenuator and the second phase shifter. The electron source device has the advantages that the beam current divergence degree is inhibited from 10<-3> to a value below 10<-5>, and the space resolution of the ultrafast electron diffraction is improved.

Description

technical field [0001] The invention relates to an ultrafast electron source, in particular to an electron source device for ultrafast electron diffraction and ultrafast electron microscope. Background technique [0002] At present, due to the great advantages of both ultrafast electron diffraction and ultrafast electron microscopy with high spatial resolution and high temporal resolution, they have gradually become important tools for studying molecular dynamics and nanostructure science. In ultrafast experiments, the time resolution is determined by the length of the electron beam. Many experiments require the electron beam to be as short as less than 100 femtoseconds and contain enough electrons, up to 10 6 Only in this way can we obtain enough sample information in a single bundle. [0003] Electron sources used in most electron diffraction and electron microscopes are electrostatic high-voltage electron guns, and the electron energy is tens of volts to hundreds of kilo...

AI Technical Summary

Problems solved by technology

[0005] In order to solve the problems of large energy dispersion of microwave electron sources, widening of electron diffraction patterns, poor spatial resolution and difficulties in electron diffraction imaging, the present invention provides an electron source device for ultrafast electron diffraction and ultrafast electron microscopy. The device can change the beam energy divergence of the microwave electron source by 10 -3 Suppress to 10 -5 following, greatly improving the spatial resolution of ultrafast electron diffraction

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