摘要
本文通过分析碱金属原子在原子气室中的自旋弛豫作用,得出了原子磁力仪灵敏度上限受气室尺寸影响的理论模型。计算了不同气室尺寸下,工作物质为87Rb、工作温度为383.15 K时缓冲气体Ar的最优压强,此压强值随气室尺寸减小而快速增大。在此基础上,计算了不同气室尺寸下磁力仪灵敏度上限。结果表明,磁力仪灵敏度上限随原子气室尺寸减小而快速恶化,当气室直径由1 cm减小到0.1 cm时,磁力仪灵敏度上限由0.4 p T Hz-1/2恶化为15 p T Hz-1/2。
The shot-noise-limited sensitivity variation due to the cells size was analyzed with the spin relaxation time of alkali atoms and the theoretical relationship was set up. According to the relationship, we calculated the optimum Ar pressure of differ-ent ^87Rb cells sizes at 383.15 K. The optimum Ar pressure increases rapidly with the cells size decreases. The magnetic sensitivi-ty limit was also calculated. The results show that the sensitivity drops rapidly with the cell size reduction. When the diameter of the cell decreases from 1 to 0.1 cm, the sensitivity drops from 0.4 to 15 pT Hz^-1/2.
出处
《真空》
CAS
2015年第4期70-74,共5页
Vacuum
关键词
原子磁力仪
自旋弛豫
灵敏度
Atomic magnetometer
Spin relaxation
Magnetic sensitivity
