CAJ | 학술논문

利用SERF原子自旋效应能够实现高灵敏度的磁场测量，碱金属原子密度与缓冲气体压强是敏感表头碱金属气室的重要参数，需要精确地测量。提出一种应用原子吸收光谱对碱金属蒸气的原子密度与压强测量方法，通过扫描碱金属原子的吸收光谱，进行 Lorentz 线型拟合，经解算同时得到原子密度和压强，一次实验获得两个物理量。由于多普勒展宽和压力展宽主要受到碱金属气室温度和缓冲气体压强的影响，从这两个方面进行了仿真分析。结果表明，充入2 amg缓冲气体时，313～513 K温度范围内的Lorentz线型与Voigt线型计算的光子吸收截面积峰值的理论误差始终小于0．015％；缓冲气体压强高于0．6 amg（393 K）时，其峰值误差小于0．1％，表明该条件下多普勒展宽对吸收光谱的影响可以忽略，可用Lorentz 线型拟合原子的吸收谱线。最后分析了该方法能够获得的理论分辨率以及激光器的功率波动、波长波动和气室温度波动对测量精度的影响，得出同等条件下温度波动的影响比其他两个因素高1～2个数量级。
이용SERF원자자선효응능구실현고령민도적자장측량，감금속원자밀도여완충기체압강시민감표두감금속기실적중요삼수，수요정학지측량。제출일충응용원자흡수광보대감금속증기적원자밀도여압강측량방법，통과소묘감금속원자적흡수광보，진행 Lorentz 선형의합，경해산동시득도원자밀도화압강，일차실험획득량개물리량。유우다보륵전관화압력전관주요수도감금속기실온도화완충기체압강적영향，종저량개방면진행료방진분석。결과표명，충입2 amg완충기체시，313～513 K온도범위내적Lorentz선형여Voigt선형계산적광자흡수절면적봉치적이론오차시종소우0．015％；완충기체압강고우0．6 amg（393 K）시，기봉치오차소우0．1％，표명해조건하다보륵전관대흡수광보적영향가이홀략，가용Lorentz 선형의합원자적흡수보선。최후분석료해방법능구획득적이론분변솔이급격광기적공솔파동、파장파동화기실온도파동대측량정도적영향，득출동등조건하온도파동적영향비기타량개인소고1～2개수량급。
High sensitivitymagnetic measurementscanbe achieved by utilizing atomic spinmanipulation in the spin-exchange-relax-ation-free (SERF)regime,which uses an alkali cell as a sensing element.The atomic number density of the alkali vapor and the pressure of the buffer gasare among the most important parameters of the cell andrequire accurate measurement.A method has been proposed and developedto measure the atomic number density and the pressure based on absorption spectroscopy,by sweep-ing the absorption line and fittingthe experiment data with a Lorentzian profile to obtainboth parameters.Due to Doppler broade-ning and pressure broadening,which is mainly dominated by the temperature of the cell and the pressure of buffer gas respective-ly,this work demonstrates a simulation of the errorbetween the peaks of the Lorentzian profile and the Voigt profile caused by bothfactors.The results indicates that the Doppler broadening contribution is insignificantwith an error less than 0. 015% at 313~513 K for a 4 He density of 2 amg,and an error of 0. 1% in the presence of 0. 6~5 amg at 393 K.We conclude that the Doppler broadening could be ignored under above conditions,and that the Lorentzianprofile is suitably applied to fit the absorp-tion spectrumobtainingboth parameters simultaneously.In addition we discuss the resolution and the instability due to thelight source,wavelength and the temperature of the cell.We find that the cell temperature,whose uncertainty is two orders of magni-tude larger than the instability of the light source and the wavelength,is one of the main factors which contributes to the error.