论文标题
Ramsey通过连贯的$ x^2σ_g^+ - a^2π_U -b^2σ_U^+$耦合和种群转移在n $^+_ 2 $ air laster中
Ramsey interferometry through coherent $X^2Σ_g^+ - A^2Π_u - B^2Σ_u^+$ coupling and population transfer in N$^+_2$ air laser
论文作者
论文摘要
从理论上研究了由强800nm泵激光和弱400nm种子激光器辐射的N $ _2 $气体在391nm处的激光样相干发射。最新的实验观察得出了充分的模拟，包括时间剖面，光学增益和来自n $ _2^+$的391nm信号的周期性调制。我们的计算阐明了长期存在的争议，即对于光学增益而言，人口反转是否必不可少。我们证明了通过另外注入800nm的泵或400nm种子形成的发射强度的拉姆西干扰条纹，这是通过过渡偶极矩的相干调节和$ a^2π_U（ν= 2）$ x^2σ_g^+$ b^2的$ a^2π_U（ν= 2）以及$ a^2π_U（ν= 2）以及（ν= 0）$ - $ x^2σ_g^+$状态。这项研究为$ \ text {n} _2^+$ air激光器的连贯控制提供了多功能的可能性。
The laser-like coherent emission at 391nm from N$_2$ gas irradiated by strong 800nm pump laser and weak 400nm seed laser is theoretically investigated. Recent experimental observations are well simulated, including temporal profile, optical gain and periodic modulation of the 391nm signal from N$_2^+$. Our calculation sheds light on the long standing controversy on whether population inversion is indispensable for the optical gain. We demonstrate the Ramsey interference fringes of the emission intensity at 391nm formed by additionally injecting another 800nm pump or 400nm seed, which are well explained by the coherent modulation of transition dipole moment and population between the $A^2Π_u(ν=2)$-$X^2Σ_g^+$ states as well as the $B^2Σ_u^+ (ν=0)$-$X^2Σ_g^+$ states. This study provides versatile possibilities for the coherent control of $\text{N}_2^+$ air laser.
