场致发射

场致发射,也叫冷发射,放电的电子从材料的表面受到强烈电场。在缺乏一个强大的电场,电子必须获得一定的最低能量,称为功函数,逃避通过给定的表面材料,充当电子通道的障碍。如果材料是放置在一个电路呈现强烈的负面对附近的积极电极(即。,when it is subjected to a strong electric field), the work function is so lowered that some electrons will have sufficient energy to leak through the surface barrier. The resulting current of electrons through the surface of a material under the influence of a strong electric field is called field emission. This effect is used in the field-emission电子显微镜在某些情况下达到解决原子维。场致发射有时被称为轨迹排放的区别肖特基效应以较低的价值,影响电子发射的应用领域。

积极的离子(原子失去了至少一个电子)也可能会发出一个坚实的承受高电场在其表面。另请参阅热电子发射。