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《2013 IEEE Sensor Journal - Atomic-Signal-Based Zero-Field Finding Technique 》由会员上传分享,免费在线阅读,更多相关内容在学术论文-天天文库。
1、186IEEESENSORSJOURNAL,VOL.13,NO.1,JANUARY2013Atomic-Signal-BasedZero-FieldFindingTechniqueforUnshieldedAtomicVectorMagnetometerHaifengDong,HongboLin,andXinbinTangAbstractWedescribeanoveltechniquethatcanfindthezerofieldinEarthsmagneticfieldforunshieldedlase
2、r-pumpedatomicmagnetometerusingatomicsignalitself.Bycomparinglightintensityofthepumpingbeamthroughatomicvaporcellunderdifferentmagneticfields,itdecideswhichdirectiontomovethecompensationmagneticfieldandwhethertoincreaseordecreasethemagnitudeofincrementsin
3、thecompensatingfield.Aconvergencecriterionisproposed,whichnotonlykeepsthefieldaroundzero,butalsogivestheprecisionofthecompensation.Thezerofieldisfoundinlessthan23sandthefieldincrementafterconvergingissmallerthan0.01,0.01,and0.04µTforthex,y,andzaxes,respecti
4、vely,limitedby50-Hznoiseinthelaboratoryenvironment.Thismethodusesonlyonelaserbeam,whichfacilitatesitsapplicationinchip-scaledevices.IndexTermsAtomicmagnetometer,convergencecriterion,laserpumping,self-test,unshieldedmagneticfield.I.INTRODUCTIONIGHSENSITIV
5、ITYmagnetometermeasuringthemag-Hneticfieldvectorsinanunshieldedenvironmenthasawiderangeofapplicationsfromgeophysicalexploration[1],underwatermetaldetection[2]todeepspaceexploration[3].AlthoughSQUIDmagnetometerorgradiometerwereFig.1.Measurementsetup.repor
6、tedtobeusedforsuchhighsensitivityapplications,theyrequirecryogeniccooling,whichincreasesthevolumeandcostofthemeasurementsystem[1],[2].Inrecentyears,thatatomicvaporcellworksunderzerofields,whichforatomicvectormagnetometerworkingunderspin-exchangethefirstti
7、medemonstratedthefeasibilityofatomicvectorrelaxationfree(SERF)regimeemergedasapromisingnon-magnetometerinthemeasurementoftheunshieldedfield[11].cryogenic,low-costalternativetoSQUIDmagnetometerwhichBecausetheearthfieldamplitudeismuchlargerthanhasachievedas
8、ensitivityofsub-fT/Hz1/2[4]–[6].However,thedynamicrangeofatomicvectormagnetometer,zeroingatomicvectormagnetometerhasaverynarrowdynamicrangethefieldusingonlyatomicsignalisextremelydifficultandandusuallyworksundershieldedenvironments