It is clear that the simple two-level atom model is too constrained to describe the behavior of such laser, and the four-level model using center-manifold techniques seems to be a particularly attractive candidate model for describingit.
英
美
- 當J=0時(shí)，四能級的振轉模型轉變?yōu)槎芗壞Ｐ?，通過(guò)理論計算的曲線(xiàn)我們可以清楚地看到二能級速率模型與四能級振轉模型的兩個(gè)主要的區別：一個(gè)FWHM(激光脈沖的全波半高寬)，從二能級模型解出來(lái)的理論曲線(xiàn)的全波半高寬與實(shí)驗結果相比明顯要窄的多；
