The rate equation theory researches the basic relation of the atomic spontaneous emission, stimulated emission and stimulatedabsorption, and it is the fundamental theoretical calculations.
速率方程表征的是原子的自发辐射、受激辐射和受激吸收几率的基本关系，是进行理论计算的根本；
2
The absorption, spontaneous emission and stimulated emission are discussed respectively.
分别考虑了吸收、自发辐射和受激辐射诸情况。
3
There are basically three processes for interaction between a photon and an electron in a solid: absorption, spontaneous emission, and stimulated emission.