tailieunhanh - Recent Optical and Photonic Technologies Part 15

Tham khảo tài liệu 'recent optical and photonic technologies part 15', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 404 Recent Optical and Photonic Technologies substituted by the averaged value Is av mW cm2. As shown in Fig. 13 the trap frequencies are in good agreement with the theoretical values. The damping coefficients on the other hand are about twice larger than the simple theoretical predictions. We provide a quantitative description of the theoretical model and explain the discrepancy found in the damping coefficient. The summary of the data of Fig. 13 is presened in Fig. 14. The damping coefficient and the trap frequency are presented as a function of s0d 1 4d2 2 and y bs0S 1 4Ổ2 respectively. Fig. 14. The damping coefficient versus s0S 1 4Ổ2 2 filled circles experimental data dashed line calculated results dashed-dotted line calculated results multiplied by and the trap frequency versus y bs0S 1 4S2 filled squares experimental data solid line calculated results . One can observe that the measured trap frequencies are in excellence agreement with the calculated results. On the other hand one has to multiply the simply calculated damping coefficients by a factor to fit the experimental data. We find that the discrepancy in the damping coefficients results from the existence of the sub-Doppler trap described in Sec. . In order to show that the existence of the sub-Doppler force affects the Doppler-cooling parameters we have performed Monte-Carlo simulation with 1000 atoms. In the simulation we used sub-Doppler forces and momentum diffusions described in Sec. . The results are presented in Fig. 15. Here we averaged the trajectories for 1000 atoms by using the same parameters as used in Fig. 12. We have varied the intensity I associated with Fsub without affecting the intensity for the Doppler force and obtained the averaged trajectory where Iexpt mW cm2 is the laser intensity used in the experiment Fig. 13 . We then infer the damping coefficient and the trap frequency by fitting the averaged trajectory with Eq. 17 . The fitted results for the .