物理学外文翻译外文翻译、英汉互译、中英对照

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1、EffectofQuantumConfinementonElectronsandPhononsinSemiconductorsWehavestudiedtheGunneffectasanexampleofnegativedifferentialresistance(NDR).Thiseffectisobservedinsemiconductors,suchasGaAs,whoseconductionbandstructuresatisfiesaspecialcondition,namely,theexistenceofhigherconductio

2、nminimaseparatedfromthebandedgebyabout0.2-0.4eV..Asawayofachievingthisconditioninanysemiconductor,EsakiandTsuproposedin1970[9.1]thefabricationofanartificialperiodicstructureconsistingofalternatelayersoftwodissimilarsemiconductorswithlayersuperlattice.Theysuggestedthattheartifi

3、cialperiodicitywouldfoldtheBrillouinzoneintosmallerBrillouinzonesor“mini-zones”andthereforecreatehigherconductionbandminimawiththerequisiteenergiesforGunnoscillations.iWiththedevelopmentofsophisticatedgrowthtechniquessuchasmolecularbeamepitaxy（MBE）andmetal-organicchemicalvapor

4、deposition(MOCVD)discussedinSect.1.2,itisnowpossibletofabricatethesuperlattices(tobeabbreviatedasSLs)envisionedbyEsakiandTsu[9.1].Infact,manyotherkindsofnanometerscalesemiconductorstructures(oftenabbreviatedasnanostructures)havesincebeengrownbesidestheSLs.ASLisonlyoneexampleof

5、aplanarortwo-dimensionalnanostructure.Anotherexampleisthequantumwell(oftenshortenedtoQW).Thesetermswereintroducedｉｎ　Ｓｅｃｔｓ．１．２　ａｎｄ　７．１５　ｂｕｔ　ｈａｖｅ　ｎｏｔ　ｙｅｔ　ｂｅｅｎ　ｄｉｓｃｕｓｓｅｄ　ｉｎ　ｄｅｔｉａｌ．Ｔｈｅ　ｐｒｏｐｏｓｅ　ofthischapteristostudytheelectronicandvibrationalpropertiesofthesetwo-dimensionalnanostr

6、uctures.Structureswithevenlowerdimensionthantwohavealsobeenfabricatedsuccessfullyandstudied.Forexample,one-dimensionalnanostructuresarereferredtoasquantumwires.Inthesamespirit,nanometer-sizecrystallitesareknownasquantumdots.Therearesomanydifferentkindsofnanostructuresandwaysto

7、fabricatethemthatitisimpossibletoreviewthemallinthisintroductorybook.Insomenanostructuresstrainmaybeintroducedasaresultoflatticemismatchbetweenasubstrateanditsoverlayer,givingrisetoaso-calledstrained-layersuperlattice.Inthischapterweshallconsideronlythebest-studynanostructures

8、.Ourpurposeistointroducereaderstothisfastgrowingfield.Onereas