Vapor cell based sodium laser guide star mechanism study lab-bench

摘要: Sodium laser guide star (LGS) is the key for success of modern adaptive optics (AO) supported large ground based telescopes, however, many field applications, LGS’s brightness still a limited factor. Large amounts theoretical efforts have been paid to optimize LGS exciting parameters, that is, fully discover potential harsh environment surrounding mesospheric extreme thin sodium atoms under resonant excitation, whether quantum or Monte Carlo based. But till now, only proposals are demonstrated with on-sky test due high cost and engineering complexities. To bridge gap between modeling test, we built magnetic controllable cell lab-bench, which includes small scale sum-frequency single mode 589nm laser, added amplitude, polarization, phase modulators. We could perform quantitative fluorescence study single, multi-frequency, side-band optical re-pumping different also modulation Larmor precession considered as one devils LGS, ability generate beams contain orbital angular moment. Our preliminary experiments shown excellent consistence Bloch equation predicted results, other experimental results will be presented in report, these give direct support lab-bench help scientists lot before their test.