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1、+第十三篇SolarPowerwithoutSolarCellsAdramaticandsurprisingmagneticeffectoflightdiscoveredbyUniversityofMichigan1researcherscouldleadtosolarpowerwithouttraditionalsemiconductor-basedsolarcells.Theresearchersfoundawaytomakean"optical1,"saidStephenRand,aprofessorinthedepartmentsofElectricalEngineer
2、ingandComputerScience,PhysicsandAppliedPhysics.Lighthaselectricandmagneticcomponents.Untilnow,scientiststhoughtthe2ofthemagneticfieldweresoweakthattheycouldbeignored.WhatRandandhiscolleaguesfoundisthatattherightintensity,whenlightistravelingthroughamaterialthatdoesnotconductelectricity,theli
3、ghtfieldcangeneratemagneticeffectsthatare100milliontimesstrongerthan3expected.4thesecircumstances,themagneticeffectsdevelopstrengthequivalenttoastrongelectriceffect."Thiscouldleadtoanewkindofsolarcellwithoutsemiconductorsandwithoutabsorptiontoproducechargeseparation,"Randsaid."Insolarcells,t
4、he5goesintoamaterial,getsabsorbedandcreatesheat.Here,weexpecttohaveaverylowheatload2.Insteadofthelightbeingabsorbed,energyisstoredinthemagneticmoment3.Intensemagnetizationcanbeinducedbyintenselightandthenitisultimatelycapableofprovidingacapacitivepower6."Whatmakesthispossibleisapreviouslyund
5、etectedbrandof"opticalrectification4,"saysWilliamFisher,adoctoralstudent5inappliedphysics.Intraditionalopticalrectification,light'selectricfieldcausesachargeseparation,orapulling7ofthepositiveandnegativecharges6inamaterial.Thissetsupavoltage,similarto8inabattery.RandandFisherfoundthatunderth
6、erightcircumstancesandinrighttypesofmaterials,thelight'smagneticfieldcanalsocreateopticalrectification.Thelightmustbeshonethrough7a9thatdoesnot10electricity,suchasglass.Anditmustbefocusedtoanintensityof10millionwattspersquarecentimeter8.Sunlightisn'tthisintenseonitsown,butnewmaterialsarebein
7、gsoughtthatwouldworkatlowerintensities,Fishersaid."Inourmostrecentpaper,weshowthatincoherentlight9likesunlightistheoreticallyalmostas.11inproducingchargeseparationaslaserlightis,"Fishersaid.Thisnew12couldmakesolarpowercheaper,theresearcherssay.They
