摘要
使用单束强聚焦的基模高斯光束可以构建光镊装载原子。虽然光镊一般选择远离原子共振跃迁线的激光,但是光镊的强度起伏仍然会导致原子逃逸,这样原子在光镊中的俘获寿命问题就变得至关重要。本实验以声光频移器(AOM)为主要元件,并施加外部反馈控制电路抑制937.7 nm波长光镊频域上的强度噪声以及时域上的功率起伏,降低光镊对原子的参量加热,从而有效延长原子在光镊中的俘获寿命。典型的频域噪声抑制带宽17 kHz,噪声强度抑制10 dB,时域内激光强度起伏可以从峰峰值起伏±1.350%抑制到±0.036%,有效地降低了光镊的强度起伏。实验结果表明我们可以将937.7 nm波长光镊中单个铯原子俘获寿命从200 ms延长至1 180 ms.为后续原子内态的制备、激发等操作提供充足的时间,保证原子处于俘获状态,提高了实验成功率,缩短了实验时长。
Using a single highly focused fundamental-mode Gaussian beam could form an optical tweezer and load atoms,although optical tweezers generally choose to far away from the atom resonance transition line of the laser, optical tweezers intensity fluctuations will also lend to the atoms’ escape,so the lifetime of the atom in optical tweezers becomes crucial.In this experiment, acoustic optical modulator was used as the main component, and a set of external feedback control circuit was added to suppress the intensity noise in frequency domain and power fluctuation in time domain of 937.7 nm optical tweezers,reducing the heating parameters of atoms in optical tweezers, so as to effectively extend the trapping life of atoms in optical tweezers.The typical bandwidth is 17 kHz,noise suppression is 10 dB, and the time-domain laser intensity fluctuation could be reduced from a peak-to-peak fluctuation of ±1.350% to ±0.036%, effectively reducing the intensity fluctuation of optical tweezers. The experimental results showed that the trapping lifetime of single cesium atom in 937.7 nm optical tweezers could be extended from 200 ms to 1 180 ms.It provides sufficient time for the subsequent preparation and excitation of atomic states, ensures the capture of atoms, improves the success rate of experiments, and saves the time of experiments.
作者
王家超
孙瑞
王欣
张孔
何军
王军民
WANG Jia-chao;SUN Rui;WANG Xin;ZHANG Kong;HE Jun;WANG Jun-ming(State Key Laboratory of Quantum Optics and Quantum Optics Devices,and Institute of Opto-Electronics,Shanxi University,Taiyuan 030006,China;Collaborative Innovation Center of Extreme Optics of the Ministry of Education and Shanxi Province,Shanxi University,Taiyuan 030006,China)
出处
《量子光学学报》
北大核心
2019年第2期180-186,共7页
Journal of Quantum Optics
基金
国家自然科学基金(11774210
61875111)
山西省"1331工程"重点学科建设计划经费资助的课题
关键词
光镊
原子俘获寿命
参量加热
激光强度噪声
强度噪声抑制
optical tweezer
trapping lifetime of atoms
parameteric heating
laser intensity noise
intensity noise suppression
