Upload
vananh
View
213
Download
0
Embed Size (px)
Citation preview
Fritz Riehle; Lecture: June 19, 2014
Singleion clocks vs.neutralatom lattice clocks
Storageof electrically charged particles inarf trap Two dimensionaltrap Paultrap in3d Penning trap
Opticalatomic clocks based onstored ions Yb
Hyper RamseySpectroscopy Quantumlogic clock Secondary representations of the second
Otherapplications of ion traps Microwave frequency standard for deep space applications Mass spectrometry
ResearchTrainingGroup1729
Ion traps for clocks and other metrological applications
Oszillator
0
Atome, Molekle oder Ionen
Detektor
Regelungs-elektronik
0
0
S
Absorptions- signal
FehlersignaldSd
oscillator
servo electronics
absorptionsignal
errorsignal
Absorber(ions,atoms,molecules)
Principle of (optical)atomic clocks
out
Opticalclockwork:femtosecondlaser
Accuracy:How accurately agrees out with 0?
Stability:Towhatextentfluctuatesout around0?
detector
Noiseand instability
104 neutralSr atoms, =429THz, =2Hz:y(t) 51017 1/2
SingleYbion, =688THz, =3.1Hz:y(t)51015 1/26105 Csatoms, =9.2GHz, =1Hz:y(t) 41014 1/2
Measure of instability(Allan deviation):
Singleionandneutralatomopticalclocks
Electrodynamic(Paul)trap
Singleionscanbeconfinedinfieldfreecenter
Trappingtime:
Neutralatomlatticeclock
104 106 atomscanbeinterrogated HighS/N;highfrequencystability Limitedtrappingtime(seconds)
NIST(Boulder)operating ,PTB,NPL,Innsbruck,under construction
Quantumlogicclock
CourtesyofP.Schmidt(QUEST)
Singleionclock
LowS/N;limitedfrequency stability
Achievable fractional instability
Assuming: Csfountain:105 Csatoms;Tint =1sec
104 Sr atoms:Tint =0.5sec
Yb+ ion:Tint =10sec
10 1 100 10 1 102 103 10 4 10 5 106 10710 18
10 17
10 16
10 15
10 14
10 13
10 12
MonthDayHour
Yb+ ion (642THz)
104 Sratoms(429THz)
Csfountain (9.2GHz)
[sec]
AllanDe
viation
6
IonTraps
FromF.Riehle,FrequencyStandards:
BasicsandApplicationsWileyVCH(2004)
QuadrupolePotential
PaulTrap(MechanicalAnalogueModel)
From:http://nobelprize.org/nobel_prizes/physics/laureates/1989/paullecture.pdf
WolfgangPaulNobelprize 1989
Realisations oflineartrapsgeneratingaradialquadrupole potentialwithtwoadditionalringelectrodesa)orwithadditionalrodsb)foraxialconfinement.
Linearion traps
Linearion trap (Innsbruckdesign2000)
11
LinearPaulTrap
Regionsofstability
Linearstrings of ions
From :Innsbruckgroup
Traponachip
Figure23:Schematicofasurfaceelectrodeiontrap.Theiontrapelectrodesareshownatthebottomofthefigureinred(RF)andblack(DC).Ionsaretrappedattheoriginofthecoordinatesystemshown.Thesecularpotentialisplottedonalinearcolorscaleasafunctionofxandy,withbluerepresentingthelowestandredrepresentingthehighestsecularpotentialvalues.
From:Leibrandt:Integratedchipsandopticalcavitiesfortrappedionquantum information processing,ThesisMIT2009
Penning Trap
Staticelectricfield+staticmagneticfield
ringelectrode
endcap
from:evB=mv2/r
Cyclotronfrequency
from:eErad =evB
Magnetronfrequency
Oscillatorymotioninz
15
IonMotioninPenning Trap
CyclotronfrequencycMagnetronfrequencym
Oscillatorymotionz
RadioFrequency (Paul)Trap
ringelectrode
endcap
z0r0
Quantumjumpspectroscopy
Thenumberofobserveddarkphasestakenfromdatalikethatofprevioustransparencyasafunctionoftheirdurationallowsonetofitanexponentialdecayandtodeterminethelifetimeofthelonglivedstate.
From:E.Peik:LaserspektroskopieangespeichertenIndiumIonen.DissertationMPQ181,MaxPlanckInstitutfrQuantenoptik,1993
Determinationof the lifetime from quantum jumps
Sidebandcooling
Absorptionspectrumofthe281.5nmtransitioninasingle198Hg+ionbefore(inset)andaftersidebandcoolingusing194nmradiation.Courtsey ofD.Wineland,withpermission
Yb+ singleionclock
E2:Chr.Tamm etal.,Phys.Rev.A89,023820(2014)
E3:N.Huntemannetal.,Phys.Rev.Lett. 108,090801(2012)
V.Yudin etal.,Phys.Rev.A82 011804(R)(2010)
E3: Insensitive to external fields E3:Extremely long natural lifetime
low instability hugelightshift
hasbeensuppressedbyHyper Ramsey Technique
Courtesy of N.Huntemann,PTB
PartialenergydiagramofYb+.Dashedlines(411nm,435nmand467nm)representtheopticaltransitionsproposedforopticalfrequencystandards.The369nmlineisusedforcoolinganddetection.
ThespectrumofthetransitionofasingleYb+ioninaPaultrapshowsbesidesthecarrierthemotionalsidebandsalongtheradial(r1andr2)andaxial(z)directions.Courtesy of Chr.Tamm.
Yb+
Currently smallest estimated uncertainty of any optical clock(comparable to Al+ NIST(8.6x1018),Sr JILA(6.4x1018))
Similarly low statistical uncertainties would require ~300hmeasuring time(could be reduced by asmaller experimentalline width;requires more stable laser)
Required:comparison of two Yb+ clocks with suchanuncertainty
Accurate measurement ofdifferentialpolarizabilityand temperature measurementinthe trap
With HyperRamseytechnique
EstimateduncertaintybudgetofPTBsYb+ clock(E3)
Courtesy of N.Huntemann
Temperatureradiationatthelocationoftheion
MeasurementwithtemperaturesensorsatacopyofthetrapandFEMbyP.BallingundM.Doleal (CMI)effec vetemperatureriseT=2(1)K
Combinationwithmeasurementofambienttemperature Frequencyshiftbythermalradiation=70.7(2.6) 1018
Courtesy of N.Huntemann
HyperRamseySpectroscopy(HRS)
Yudin etal.,Phys.Rev.A82 011804(R)(2010)Huntemannetal.,Phys.Rev.Lett. 109 213002(2012)
CompensationofthelightshiftL bydetuningS oftheclocklaserduringinterrogation
Additional pulseremoveslinearbehaviour ofLSconsiderablesuppressionoflightshift
ExperimentalinvestigationofHRS
RealtimestabilizationoffrequencyjumpSguarantees(LS)=0Huntemannetal.,Phys.Rev.Lett. 109 213002(2012)
PrincipleoftheAl+ Clock
LaserOscillator fscomb
8:52amQuantumLogicStateDetectionFrequency
Feedback
280THz=1070nm
x4
I(f)
f
Al+Ca+
quantum logic
2P3/2
2D5/2
2S1/2
397nm
729nm
866nm
854nm
I=0
2P1/2
2D3/2
40Ca+
coolingand
detection
I=5/2
clock
3P1
1S0
167nm
267.4nm
1P1
3P0logic267nm
27Al+Courtesy of P.Schmidt
Quantumlogic ion technique
a)Clock ion and logicionareintheirelectronicandmotionalgroundstates.b)Excitationoftheclockion.c)Apulsedetunedtothebluemotionalsidebandmapstheexcitationamplitudesandoftheclockionontothemotionalstatesoftheclockionand,asaresultoftheentanglement,thelogicion.
d)Apulsedetunedtotheredmotionalsidebandmapsandontheelectronicstatesofthelogicion.
Al+ clock
Al+ clock (instability and accuracy)
f(Al+)/f(Hg+)=1.052871833148990438(55)
f(Hg+)=1064721609899145.30(69)Hz.
T.Rosenbandetal,Science319(2008),1808 1812
31
Influence of special relativity
1905"ZurElektrodynamikbewegterKrper"
Principleofrelativity:LawsofPhysicsarethesameinallinertialsystems
c=const:Thespeedoflighthasineachinertialsystem(invacuum)thesamevalue(c=299792458m/s).
t:Timeintervalinaninertialsystem,movingw/rtoasecondonewithvelocityv.t:Timeintervalasobservedfromthesecondinertialsystem.
Spaceandtimearenolongerabsolute!
Timedilation:movedclocksslowdown
Al+ quantum logic clock relativistic tests (I)
C.W.ChouandD.B.HumeandT.Rosenband andD.J.Wineland:OpticalClocksandRelativity;Science329 (2010)1630 1633
Relativistic timedilation
Theory of GeneralRelativity
Largemass(sun,earth)
Theoryofgeneralrelativity(1915)frominertialsystemsofspecialrelativitytoacceleratedsystems
Equivalenceprinciple:Gravitationandaccelerationareequivalent
Result:Gravitationmodifiesspace(curvature)andslowsdowntime
Curvatureofspace
Matter(density,pressure,..)
Fundamentalconstants
Metric tensords2=g (x)dx dx
metric tensor inasuitable coordinate system (x) = (x0, x1, x2 x3)
Metrictensorforanonrotatinggeocentriccoordinatesystem:
with U=UEarth +UTide:Newtonian gravitational potential
Near Earths surface the approximation holdsU~ghwith g~9.81m/s2and h:height/ ~gh/c2~1.1. 1016 h
C.W.ChouandD.B.HumeandT.Rosenband andD.J.Wineland:OpticalClocksandRelativity;Science329 (2010)1630 1633
Al+ quantum logic clock relativistic tests (II)
h =33cm
Relativistic timevariation inagravitational potential
Inthefutureanewdefinitionforthesecondwillberequired.
Opticalclocksvs.Csclocks Status2014
PrimaryCsclocksOpticalfrequencies (relativeto Cs)Estimated uncertainties of optical standards
year
fractio
naluncertainty
Adoption as such secondary representations would help with detailedevaluation of reproducibility of these standards at the highest level
Such systems could be used to realise the second, provided their accuracy was close to that of caesium
Optical and other micowave standards were expected to demonstratereproducibility and stability approaching that of primary caesium
Their uncertainty could obviously be no better than the caesiumuncertainty
This activity was likely to significantly aid the process of evaluation of different standards in preparation for a possible future redefinition of the second
In2001CCTFhas established aworking group,that developed the concept,procedures and recommendations (now CCL CCTFWGFS).
Secondary representations of the second
Criteria for asecondary representation
2)Thisuncertaintyshouldbenolargerthanaboutafactorof10oftheprimarystandardsofthatdatethatserveasthebestrealisationsofthesecond.
1)TheSIvalueoftheunperturbedfrequencyofaquantumtransitionsuitableasasecondaryrepresentationofthesecondmusthaveanuncertaintythatisevaluated anddocumentedsoastomeettherequirementsadoptedfortheprimaryfrequencystandardforuseinTAI.
Secondary Representations of the Second
System Studied at Value / Hz Relative uncertainty
27Al+ NIST, PTB 1 121 015 393 207 857.3 1.9 x 10-15
199Hg+ NIST 1 064 721 609 899 145.3 1.9 x 10-15
171Yb+ (E2) PTB, NPL 688 358 979 309 307.1 3 x 10-15
171Yb+ (E3) PTB, NPL 642 121 496 772 645.6 1.3 x 10-1588Sr+ NPL, NRC 444 779 044 095 485.3 4.0 x 10-1587Sr PTB, SYRTE,
U. Tokyo, JILA, NIMJ, NPL,
429 228 004 229 873.4 1 x 10-15
171Yb NIST, 518 295 836 590 865.0 2.7 x 10-1587Rb SYRTE, NPL,
6 834 682 610. 904 312 1.3 x 10-15
Theseoptical clocks can be used alternatively to the Csclock,butcan never have anuncertainty better than the Csclock.
(CIPM2012)
Application 1:Deep SpaceAtomic Clock
Microwave IonTrap(199Hg+)
IntheJetPropulsionLaboratoryultrastablefrequencystandards[basedonlineartrapswithtypically106to107 199Hg+ ionspumpedbya202Hgrf dischargelampandcooledwithHebuffergastonearroomtemperature.
Microwave IonTrap(199Hg+)for deep space applications
InanextendedlineartrapionsaretransferredbetweentwoconfinementregionsoneforproductionanddetectionoftheionsandoneforRamseyexcitation.ThecontributionofthefractionalsecondorderDopplershiftwasestimatedtobe4 1013.
2.29cmx26cmx23cm;17,5kg;44W
From:https://directory.eoportal.org/web/eoportal/satellitemissions/d/dsac
https://directory.eoportal.org/web/eoportal/satellite
Microwave IonTrap(199Hg+)for deep space applications
Application 2:LinearPaulTrapas Mass Filter
From:http://nobelprize.org/nobel_prizes/physics/laureates/1989/paullecture.pdf
LinearPaulTrapasMassFilter
Resolvingpowerm/m=6500
From:http://nobelprize.org/nobel_prizes/physics/laureates/1989/paullecture.pdf
IonTrapMass Spectrometry inSpace
PtolemyInstrumentandtheRosettaSpaceMission
J.F.J.Todd,S.J.Barberetal.J.MassSpectrom. 2007;42;110
Cometsaresmallbodiesthatorbitthesuninoursolarsystem
Cometscompriseofrock,dustandice Nucleusissmallerthan50km,thetail(coma,
etc.)canbeverylarge upto150millionkm(largerthanthesun)
Cometsareusuallyverydarkobjects:onlyfew%ofmassreflectlight
Cometsconsistofmaterialformedattheformationoftheearth(+otherplanets)frozenintime(4600millionyearsago)
CometHaleBopp(03/21/97)
RosettaMission LaunchedMar2004onAriane 5G+inKourou,French
Guyana DesignedtomeetupwithcometChuryumov
Gerasimenko (67P)in2014 3000kglaunched(100kglander,165kgscientific
instruments) Flybyseveralothercometsuntilthelanding Fullyautomaticlanding Totalcost:$970980million
2004
2005
02/2007
11/2007
05/2014
PtolemyInstrumentonRosettaLander
Mass Spectrometer of Ptolemy
Measure2H,13C,15N,17Oand18Orelativetospecifiedreference
http://ptolemy.open.ac.uk/frames.htm
http://ptolemy.open.ac.uk/frames.htm
KATRIN:KarlsruheTritiumNeutrinoExperiment(75mlong)
Application 3:Mass spectrometer for neutrino restmasshttp://depts.washington.edu/uwptms/pics/dp7neutrino.png
Fritz Riehle; Lecture: June 19, 2014
Singleion clocks vs.neutralatom lattice clocks
Storageof electrically charged particles inarf trap Two dimensionaltrap Paultrap in3d Penning trap
Opticalatomic clocks based onstored ions Yb
Hyper RamseySpectroscopy Quantumlogic clock Secondary representations of the second
Otherapplications of ion traps Microwave frequency standard for deep space applications Mass spectrometry
ResearchTrainingGroup1729
Ion traps for clocks and other metrological applications
Foliennummer 1Principle of (optical) atomic clocksFoliennummer 3 Single ion and neutral atom optical clocksFoliennummer 5Foliennummer 6Foliennummer 7Foliennummer 8Foliennummer 9Foliennummer 10Foliennummer 11Foliennummer 12Foliennummer 13Foliennummer 14Foliennummer 15Foliennummer 16Foliennummer 17Foliennummer 18Foliennummer 19 Yb+ single ion clockYb+Foliennummer 22Foliennummer 23Foliennummer 24Foliennummer 25Foliennummer 26Principle of the Al+ ClockQuantum logic ion techniqueAl+ clockAl+ clock (instability and accuracy)Foliennummer 31Al+ quantum logic clock - relativistic tests (I)Foliennummer 33Foliennummer 34Foliennummer 35Foliennummer 36Foliennummer 37Criteria for a secondary representationFoliennummer 39Foliennummer 40Foliennummer 41Foliennummer 42Foliennummer 43Foliennummer 44Foliennummer 45Foliennummer 46Foliennummer 47Foliennummer 48Foliennummer 49Application 3: Mass spectrometer for neutrino rest massFoliennummer 51