The extra electron fills up the lower-energy state in the conduction band, causing excited electrons to, effectively, spill over into the higher-energy, photon-emitting state.

这个额外的电子填充了传导带的较低能级，有效的导致了被激发的电子溢入较高，释放光子的能级。

youdao

When an electron leaps into the conduction band, it leaves behind a hole in the valence band.

当一个电子跃迁到传导带，它会在价带留下一个“凹陷”。

youdao

These are photodetectors, band gap two electron volts, respond to visible light.

这是光电探测器，能带隙为2电子伏，当它反应于可见光。

youdao

These are photodetectors, band gap two electron volts, respond to visible light.

这是光电探测器，能带隙为2电子伏，当它反应于可见光。

麻省理工公开课 - 固态化学导论课程节选