学科分类
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3 个结果
  • 简介:Metasurfaceshavebecomeanewphotonicstructureforprovidingpotentialapplicationstodevelopintegrateddeviceswithsmallthickness,becausetheycanintroduceanabruptphasechangebyarraysofscatterers.Tobeappliedmorewidely,activemetasurfacedevicesarehighlydesired.Here,atunableterahertzmeta-leuswhosefocallengthisabletobeelectricallytunedby-4.45λisdemonstratedexperimentally.Thelensconsistsofametallicmetasurfaceandamonolayergraphene.Duetothedependenceoftheabruptphasechangeofthemeta-surfaceonthegraphenechemicalpotential,whichcanbemodulatedusinganappliedgatevoltage,thefocallengthischangedfrom10.46to12.24mmwhenthegatevoltageincreasesfrom0to2.0V.Experimentalresultsareingoodagreementwiththetheoreticalhypothesis.Thistypeofelectricallycontrolledmeta-lenscouldwidentheapplicationofterahertztechnology.

  • 标签: 散射体阵列 光子结构 通讯技术 发展现状
  • 简介:LinuxbasednetworkedPCsclustersarereplacingboththeVMEnonuniformdirectmemoryaccesssystemsandSMPsharedmemorysystemsusedpreviouslyfortheonlineeventfilteringandreconstrucion.ToallowanoptimaluseofthedistributedresourcesofPCclustersanopensoftwareframeworkispresentlybeingdevelopedbasedonadataflowparadigmforeventprocessing.Thisframeworkallowsforthedistributionofthedataofphysicseventsandassociatedcalibrationdatatomultiplecomputersfrommultipleinputsourcesforprocessingandthesubsequentcollectionoftheprocessedeventsatmultipleoutputs.Thebasisofthesystemistheeventrepository,basicallyafirst-infirst-outeventstorewhichmaybereadandwritteninamannersimilartosequentialfileaccess.Eventsarestoredinandtransferredbetweenrepositoriesassuitablylargesequencestoenablehighthroughput.Multiplereaderscanreadsimultaneouslyfromasinglerepositorytoreceiveeventsequencesandmultiplewriterscaninserteventsequencestoarepository,Hencerepositoriesareusedforeventdistributionandcollection.Tosupportsynchronisationoftheeventfolowtherepositoryimplementsbaaiers.Abarriermustbewrittenbyallthewritersofarepositorybeforeanyreadercanreadthebarrier,Areadermustreadabarrierbeforeitmayreceivedatafrombehindit.Onlyafterallreadershavereadthebarrieristhebarrieremovedfromtherepository.Abarriermayalsohaveattacheddata,Inthiswaycalibrationdatacanbedistributedtoallproessuingunits.Therepositoriesareimplementedasmulti-threadedCORBAobjectsinC++andCORMAisusedforalldatatransfers,JobsetupscriptsarewritteninpythonandinteractivestatusandhistogramdisplayisprovidedbyaJavaprogram.JobsrununderthePBSbatchsystemprovidingshareduseofresourcesforonlinetriggering,offlinemassreporcessinganduseranalysisjobs.

  • 标签: H1实验 数据流 数据处理
  • 简介:Polarizationmanipulationisasignificantissueforartificialmodulationoftheelectromagnetic(EM)wave,butgeneralmechanismsallsuffertherestrictionofinherentsymmetricpropertiesbetweenoppositehandedness.Herein,astrategytoindependentlyandarbitrarilymanipulatetheEMwavewithorthogonalcircularpolarizationsbasedonametasurfaceisproposed,whicheffectuallybreaksthroughtraditionalsymmetricalcharacteristicsbetweenorthogonalhandedness.Bysynthesizingthepropagationphaseandgeometricphase,theappropriateJonesmatrixiscalculatedtoobtainindependentwavefrontmanipulationofEMwaveswithoppositecircularpolarizations.Twotransmissiveultra-thinmeta-deflectorsareproposedtodemonstratetheasymmetricalrefractionoftransmittedcircularlypolarizedwavesinthemicrowaveregion.Simulatedtransmittedphasefrontandmeasuredfar-fieldintensitydistributionsareinexcellentagreement,indicatingthatthetransmittedwavewithdifferentpolarizationscanberefractedintoarbitraryandindependentdirectionswithinawidefrequencyband(relativebandwidthof25%).TheresultspresentedinthispaperprovidemorefreedomforthemanipulationofEMwaves,andmotivatetherealizationsofvariouspolarization-independentpropertiesforallfrequencyspectra.

  • 标签: Polarization MANIPULATION general mechanisms effectually BREAKS