Ributions of sodium atoms with recoil for I = 50 W/m2 , one hundred W/m2 , and 150 W/m2 for 0 MHz linewidth.Atmosphere 2021, 12,9 ofFigure 5. Normalized distributions of sodium atoms with linewidth broadening for I = 50 W/m2 , one hundred W/m2 , and 150 W/m2 for 0 MHz linewidth.Figure four shows that high Oxyfluorfen Autophagy intensity causes far more drastic recoil and aggravates the adverse scenarios. Simultaneously, the larger intensity tends to make sodium atoms drift for the greater Doppler 4′-Methoxychalcone Purity frequency shifts. Figure 5 reveals that the linewidth broadening strategy can successfully alleviate the recoil effects for different laser intensities. four.two. Decision of Optimal Laser Linewidth In practice, in the event the recoil effects need to be dropped, plus the laser is required to modulate the intensity distribution in Equation (five). The linewidth broadening with the laser intensity distribution aims at reaching the maximal excitation probability of mesospheric sodium atoms. The maximal average spontaneous emission rate is essential. As a result, we simulate the typical spontaneous emission rates by the linewidth broadening from 0 to 1.0 GHz. In light of Equations (two)9), the average spontaneous emission prices together with the intensity from 0 to 1500 W/m2 are simulated in Figures six and 7.Figure six. Typical spontaneous emission prices vs. linewidth and intensity from five to 150 W/m2 .Atmosphere 2021, 12,10 ofFigure 7. Average spontaneous emission rates vs. linewidth and intensity from 150 to 1500 W/m2 .Figures 6 and 7 show that the peak values of average spontaneous emission rates transform together with the laser linewidth and intensity. The high intensity enhances the peak values of average spontaneous emission rates. When the laser is broadened to a bigger linewidth, the typical spontaneous emission rates rather drop. In the case of lower intensity, the laser linewidth broadening finitely gains the typical spontaneous emission prices within the range of l00 MHz. Having said that, it is not that the wider linewidth can receive the best impact, but that the typical spontaneous emission prices have a maximum for the linewidth from 1 MHz to one hundred MHz. Even so, L the typical spontaneous emission price at v D = 0 MHz is lower than the peak values. In Figures six and 7, the peak values of average spontaneous emission prices would be the exact same in terms of linewidth. We hope that the linewidth broadening of laser intensity distributions tends to make the average spontaneous emission rate maximal. Figures eight and 9 simulate the average spontaneous emission rates for laser linewidth from 1 to 103 MHz and laser intensity from 5 to 1500 W/m2 .Figure 8. Typical spontaneous emission prices for laser linewidth from 3 to 103 MHz and laser intensity I = five – 150 W/m2 .Atmosphere 2021, 12,11 ofFigure 9. Typical spontaneous emission rates for laser linewidth from three to 103 MHz and laser intensity I = 150 – 1500 W/m2 .Figures eight and 9 indicate that the peak values of typical spontaneous emission prices are in between 1 MHz and 100 MHz for an intensity from 5 W/m2 to 1500 W/m2 . Hence, the laser linewidth is taken as the value amongst 1 MHz and 100 MHz. Figure ten demonstrates L the relation amongst laser linewidth at v D = 0, 1, ten, one hundred MHz and typical spontaneous emission rates. L By comparing typical spontaneous emission prices for every single linewidth at v D = 0, 1, L =0 MHz and ap10, one hundred MHz, the typical spontaneous emission rates are lowest at v D L proximately equal for linewidth at v D = 1, ten, 100 MHz. This implies a lot more return photons L = 1, ten, one hundred MHz. The laser linewidth at v L = ten MHz i.