color switching of a terahertz quantum cascade laser martin a. kainz资料.pdf

该【color switching of a terahertz quantum cascade laser martin a. kainz资料 】是由【dt83088549】上传分享，文档一共【6】页，该文档可以免费在线阅读，需要了解更多关于【color switching of a terahertz quantum cascade laser martin a. kainz资料 】的内容，可以使用淘豆网的站内搜索功能，选择自己适合的文档，以下文字是截取该文章内的部分文字，如需要获得完整电子版，请下载此文档到您的设备，方便您编辑和打印。RESEARCHARTICLE|;SebastianSch?nhuber;BenediktLimbacher;;HermannDetz;GottfriedStrasser;GéraldBastard;,191104(2019)https:///??CrossMarkViewExportOnlineCitation25July202305:12:40/journal/aplColorswitchingofaterahertzquantumcascadelaserCiteas:,191104(2019);doi::::,1,2,a)SebastianSchonhuber,€1,2BenediktLimbacher,1,,2,3HermannDetz,2,4GottfriedStrasser,2,3GeraldBastard,1,5andKarlUnterrainer1,2AFFILIATIONS1PhotonicsInstitute,TUWien,1040Vienna,Austria2CenterforMicro-andNanostructures,TUWien,1040Vienna,Austria3InstituteofSolidStateElectronics,TUWien,1040Vienna,Austria4CentralEuropeanInstituteofTechnology,BrnoUniversityofTechnology,61200Brno,CzechRepublic5LaboratoiredePhysiquedel’EcoleNormaleSuperieure,PSLResearchUniversity,75005Paris,Francea)Electronicmail:martin.******@:12:,populationandelectronscatteringeffectsforthetwostatesareinvestigatedatdifferentoperatingic?,thepopulationofstatej3iiscontinuouslyreduced,?eld,theelasticscatteringchannelfromj4i!j3iisprogressivelysuppressed,(s).Allarticlecontent,exceptwhereotherwisenoted,BY)license(http:///licenses/by//).https:///(QCLs)intheterahertzfrequencyrangeusingathree-wellactiveregiondesignwitharesonantLO-phononesigni?-,10Toincreasethistemperature,differentmentshaveenabledlasingupto200K,2amaximumoutputpowerofactiveregiondesignswerestudied,includingtwo-welldesigns,11,121W,-phonondepopulationdesigns,,novel?forthedesignofbroadbandlaserstructuresandactiveregionswithmaterialsystemswithalowereffectiveelectronmassmewerestudied,?à3=215highmaximumoperatingtemperatures(Tmax).(Ga)AlAs,16–19InGaAs/GaAsSb,-,?-’sfunctionsmethod22orusingaaddthegainbandwidthofeachsubactiveregionandhasenabledMonteCarloapproach23canbeusedtodescribethegainpro?leofter-octave-spanningemissionforterahertzQCLs,-domainspectroscopymeasurementspro-?le24andgainHighoperatingtemperaturesforterahertzQCLsareanongoingdynamics25,26andcanbeusedtoimprovetheperformanceofactivechallengesincetheir?,,whichwasachievedbyprocessesistostudythedominantscatteringmechanisms(,191104(2019);doi:,191104-1VCAuthor(s)2019/journal/aplandelectron-electronscattering)(f42andf32).Tocalculatethespectralgainpro?leic??elds,weuseasimplemodelbasedThedeviceperformanceofterahertzQCLsismodi?eddramaticallyonthecalculationofthespectralgaincross-section32ic??;(1)0nrefLkieTEiàhxtcterahertzQCL,ic?,,n?,ic?eld,resultingin190Kat11TforInGaAs/GaAsSbandref31kisthewavelengthforeachtransition,c?1meVistheassumed195Kat12TforInGaAs/,,weinvestigateadual-aAs/AlGaAsiFigure1(b)binedgaincross-sectionoftransitionLTterahertzQCLwithtwoupperlaserstatestostudythein?uenceofthe32andLTforbias?à1,wherepare42alinearoffsetinthey-?elds,themainpartofthegainislocatedatLT,mechanismsforthepopulationofthetwoupperlaserstates,weapply42whichchangestotransitionLTforhigherbias?,aic?eldparalleltothegrowdirectionand?ndforhigherB-32blueshiftcanbeseenforbothtransitionsinducedbytheStarkeffect.?(c)showsmultimodelasingandtwosepa--wellactiveregionwithanalumi-energydifferenceofDE?%inthebarriertosuppresselectronleakagetheenergydifferenceoftheinjectorandupperlaserstateE43obtainedatelevatedtemperatures,resultinginTmax?-metalwaveguidefrombandstructurecalculationsdonewitha1-dimensional€geometrytoensurehighmodecon?-coloremission,ourQCLstructureFormultimodelasing,nickelsideabsorbersareaddedintheprocess-(a)showsthelasingtransitionsoftheinvestigatedthree-forunderstandingtheinjectionprocessandprovidesapossibilityfor25July202305:12:40welldesignatbias?à;j3i,,!j2iandj4i!j2i,-extractionstate,whichisef?cientlydepopulatedbyaLO-phononperatures,theprocessedsamplesaremountedonthecold?ngerofaparedtoothercontinuous?-wellquantumcascadestructures,2,10theinjectorbarrierofthiswithaparabolicmirrorandguidedintoaFourier-(FTIR)spectrometerwithanintegrateddeuteratedtriglycinesulfateresultsinasmallenergyseparationbetweentheinjectorlevelj4iand(DTGS)(a)showsthelight–current–volt-theupperlaserlevelj3iofE?(LIV)measurementsatheatsinktemperaturesof5K,80K,,respectively),thedevice(2550mlongand120lmwide,witha15lmnickelsideabsorber)isdrivenwithapulselengthof500nsandarepetitionrateof10kHz(%dutycycle)(b).Foralltemperatures,-section,(c)].Forthetwolowtemperaturemeasurements,transitionLT32appearsforhighercurrentdensitiesandthushigherbias?elds,whereasforthemeasurementat140K,,thewideinjectorbarrierpre-.(a)Bandstructureoftheinvestigateddesignfortwodifferentbias?à1ventsasuf?cientpopulationofstatej3iandreducesthelasingtransi-,?à1.(b)Spectralgaincross--section,calculatedthetwotransitionscalculatedwithEq.(1)à1.(c)Lasingwitha1-DSchrodinger€solver,cannotexplaintheobtainedspectralspectrumatatemperatureof5Kshowingtwolasingbandsbelongingtothetransi-modeformation,,191104(2019);doi:,191104-2VCAuthor(s)2019/journal/.(a)Light–current–voltagemeasurementforheatsinktemperaturesof5K,80K,.(b):12:.(a)ic?elddependentLIVmeasurementsatLHetemperature.(b)Schematicoftheusedsetup.(c)?eldB.(d)ic?.(e)-sectioncalculation,ic?elds(B?0T,,).?à-sectionalsoFigure3(c)showsthethresholdcurrentdensityJthandthemaxi-predictsablueshiftforLT42,thespectrashowthatthistransitionisfre-?-ismorelocalizedatthedopedinjectorwellandthespacechargethereateB-?eldsupto3T,,-B-?elds,whichisaresultofthereducednonradiativescatteringpro-tiallyseparatedindifferentQuantumCascadeperiodsduetothefor-?eldshigherthan6T,Jthincreasesagain,whichmationofelectric?,weapplyamag-LT42,?,weinvestigatethescatteringinducedinteractionFigure3(d)ic?eldsof0T,,,whichbelongtotheoperationpointsmarkedinthelight–currentThemeasurementsareperformedinacryostatwithasupercon-(a),wherethetransitionsLT32andLT42arecoloredic?,(1900lmlongand90lmwide,witha10lmnickelsideabsorber)(e).ForB?0T,thetransitionLT32ismountedonaprobe,whichisimmersedinliquidhelium(LHe)[,whileforB>1T,ic?eld3(b)].-reducestheelasticscatteringfromj4itoj3iandchangestheelectronnetic?-planecon??eldenergystatesjiisplitintoasetofequidistantLandaule