無序d波超導體態(tài)密度的弱局域化修正.pdf

1、分類號UDC密級：——壘n一學吼一旦墊!≥墜一東南大學碩士學位論文無序d波超導體態(tài)密度的弱局域化修正研究生姓名：直主導師姓名：揚丞塞夔援中請學位級別亟學科專業(yè)名稱超塞查塑堡論文提爻日期!Q墮壘曼旦一學位授予單位苤童盍堂一答辯委員會主席里囂，麴垣論文答辯日期一20一皇生i基墨!旦學位授予二j期一!旦墮生縣旦評閱八一翌鑫猿一重塹擅～王鞋目L割塹撞2005年3月i5習東南大學碩士論文AbstractAnumberofexperimentals

2、tudiesrevealedthattheorderparameterinhigh—Tccupratesisofd—wavesymmetryandthusthepropertiesofd—wavesuperconductorshavebeeninvestigatedtheoreticallyformanyyearsTheissuethatthedisordereffectduetoimpurityscatteringonfeatures

3、ofdwavesuperconductorshasbeenreceivedmuchattentionManynumericalandanalyticalworkssuggestedthattheweaklocalizationeffecthasimportantinfluenceonquasiparticledensityofstatesandtransportpropertiesindwavesuperconductorsInthis

4、paperwestudytheweak—localizationeffectduetOnonmagneticimpurityscatteringonthedensityofstatesindwavesuperconductorsAlthoughtherehavebeenexistedsometheoreticalworksonthisproblem，theweak—localizationtheoryisnotwellestablish

5、ed，andtheresultsareindisagreementThetight—bindingmodelfortwodimensionalsquarelatticeisusedtOstudythelow。energydensityofstatesaroundnodalpointsindwavesuperconductorsWiththedia—grammatictechniquesandselfconsistentTmatrixap

6、proximation，weobtaintheone—particleGreen’Sfunctionsofdwavesuperconductors，andderivetheexpressionsofthediffusivemodesThequantuminterferencecorrectiontothedensityofstatesduetothesemodesarccalculated，andthemainresultsareasf

7、ollows(1)ForgenericFermisurface，onlythe0modeeooperoncontributestotheweaklocalizationcorrectiontodensityofstates，whichisoflogarithmicsuppression(2)InthecaseofnestingFermisurfaceandunitarylimit(ONlimit)，thoseselfenergydiag

8、ramswithtWOnmodediffusonshaveadditionalcontributionstothedensityofstatesTherefore，thedensityofstatesissubjecttoanegativecorrectionThisresultisqualitativelydifferentfrompreviousoneThepresentworkisexpectedtobehelpfulinunde

9、rstandingthedensityofstatesindisordereddwavesuperconductorsOurmainnewresultsareasfollows：(1)Thedetailedderivationsofthediffusivemodesindwavesuperconductorsarepresented，whichwerenotpro—videdinthepreviousworks；(2)Wefindsom

10、enewselfenergydiagramswithtwoⅡ一modediffusions，whichwereneglectedbypreviousworkersThesenewdiagramsareshowntohaveimportantinfluenceonthedensityofstatesintheUNlimit，andthusleadstoaresultqualitativelydifferentfromtheprevious