Plasmon enhancement based electron emitting device and method with light enhancement/modulation

Abstract

The present invention discloses a plasmon enhancement based electron emitting device and method with light enhancement / modulation. The device includes: a package structure, a power source and a light source, wherein the package structure has a cathode and an anode; a through hole is formed in the anode, the cathode is disposed on a conductive substrate, and the cathode is a field-emission cathode constituted by a cathode substrate and metal nanostructures attached to a surface of the cathode substrate; the power source forms an electric field between the cathode and the anode; and the light source emits laser light incident on the metal nanostructures of the cathode through the through hole of the anode. In the light enhancement / modulation electron emission device of the present invention, the incident light emitted by the light source causes enhancement of the electron emission of the field-emission cathode which is formed by combination of field-emission material of the cathode substrate and the metal nanostructures, so that the electron emission efficiency is increased. Meanwhile, by changing the intensity, wavelength and polarization of the incident laser, a local field of the surface of the field-emission material is adjusted, and light modulating electron emission is achieved.

Description

technical field [0001] The light enhancing / modulating electron emission device of the present invention can be applied to high-frequency electronic devices, ultrafast electron sources, and free electron lasers. Background technique [0002] For the field electron emission of fixed materials, the emission ability is mainly determined by the potential barrier between the cathode material and the vacuum level, the energy of the internal electrons and the magnitude of the external electric field. The higher the energy of the internal free electrons, the greater the external electric field. Larger, the easier it is for electrons to tunnel to the vacuum level. In order to obtain an electron source with modulation characteristics, the external voltage can be modulated by electrical methods to achieve modulation characteristics, but this method cannot meet the requirements of ultrafast electron sources due to the limitation of the frequency characteristics of the electrical device i...

AI Technical Summary

Problems solved by technology

In order to obtain an electron source with modulation characteristics, the external voltage can be modulated by electrical methods to achieve modulation characteristics, but this method cannot meet the requirements of ultrafast electron sources due to the limitation of the frequency characteristics of the electrical device itself; in addition to electrical modulation, it can also be used The photon characteristics of the incident laser make the electrons inside the cathode material absorb photon energy, which increases its own energy and increases the probability of tunneling to the vacuum level

At present, the cathode materials in this method are mainly concentrated in alkali metals, noble metals and other materials. Due to the relatively high requirements for packaging of alkali metals, the quantum efficiency of noble metal cathodes is relatively low.

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