Spin-dependent tunneling junctions with amorphous CoNbHfFe Manish Sharma, Lung T. Tran, Thomas C. Anthony Benédicte Warot1, Amanda K. Petford-Long1

Information Access Laboratory HP Laboratories Palo Alto HPL-2002-189 September 9th , 2002* E-mail: manish_sharma@hp.com We report on using amorphous Co77Nb16Hf6Fe1 (CoNbHfFe) as the

ferromagnetic electrode in bottom-pinned magnetic tunnel junctions (MTJ's). Exchange bias with CoNbHfFe was achieved with Mn75Ir25 as the antiferromagnetic pinning layer. In a first sample with both pinned and sense layers being CoNbHfFe, a tunnelling magnetoresistance ratio (TMR) of 5% was found. In comparison, a TMR of 16.4% was found in a second sample with a pinned Co50Fe 50 electrode and a sense CoNbHfFe electrode. This leads to a low spin-polarization of about 15% for CoNbHfFe at room temperature. High-resolution transmission electron microscopy (HREM) images show that while the first sample has a fully amorphous sense layer, the sense layer in the second sample is largely amorphous with nano-crystalline inclusions. Both pinned layers are found to be highly textured and crystalline. To study switching distributions, large MTJ arrays were patterned using electron-beam lithography and the magneto-optic kerr effect (MOKE) was used to measure the switching of the sense layer. MOKE results for the two samples are compared in arrays with devices of different sizes.

* Internal Accession Date Only Approved for External Publication 1 Department of Materials, University of Oxford, Parks Road, Oxford, OX1 3PH, UK Copyright Hewlett-Packard Company 2002

"!#$%'&)(*,+-% ./,02135476

8:9<;=?>A@CB@9DAEF9HGJILKNM;OQPRSPDT9<;UG,9<;HV"PW@HXYEZ9>L[\R^]\;`_T@HXY;`abdcfeWghcfijilknmporqts<o<uvxwUo`yfzuo<i|zufnct~t`r<FmWorcd:ggzo`vmpo<ghz\giz-fHNd

;VH=h_A:9<DAX<_Z9<;V]\EF9<;V9/R f_A¡¢XYDV£KNXY;O¤¥c|¦Ho<u7ij§Zcf¨iLz©ªQo<i|cfu7jo<gJ~t«¨¬<cfut~fij­Cz©¯®S°A©±zuv

mpo<uTs~²zo`v³®S°A©±zuv´®µ Cm,b¯U¶ ·¹¸º±»|¼7½-¾^¿<¼tÀÁ»|¼7ÂütÄÅ<ÆDZÈÈÉÇÉÊ

ËÍÌ)αÏÐÑÒ`ÏÓ ¼Ä¼tÀÔÄ»ÔÉÕxÖÁ×ØÙÕ`Ú ºÂÔÄÀrÛÁÔÉÖÁ×ÜÝÔÞ|ÞTß,Ãàjátâã¹áAäÁ¼Éà·¢Ü^ÔÉß,Ãrâã¹ä`¼±Ê,º×p»Û`¼\ã?¼tÄÄÔÉÂ庱ÚÉÕ`¼t»ØÙæ\¼7ç¼7æT»|ÄÔY½`¼ØÙÕ

ÃÔ»|»|ÔÉÂè¢ÀrØÙÕrÕ`¼7½xÂ庱ÚÉÕ`¼t»ØÙæ\»ÖÁÕÁÕÁ¼7çÁéÖÁÕÁæT»ØÙÔÉÕÁ×·êLë,ìÁíî×ÊïðNñ`æÛÁºÕ`Ú¼ÃØÙº×ò,Ø»ÛóÜÝÔÉßÃrâ,ã¹ä`¼ò^º×ºæÛrؼtô¼7½ò,ػۯêLÕ Þ$õAö Ä÷ õ º×ø»Û`¼LºÕ»Øã?¼tÄÄÔÉÂ庱ÚÉÕ`¼t»ØÙæùÀrØÙÕÁÕÁØúÕ`ÚZçúº7û¼tÄ7ï ö Õ¯ºªüÁÄ×»å׺ÂÀrç¼òػ۳ÃÔ»Û³ÀrØÙÕrÕ`¼7½³ºÕÁ½×|¼7ÕÁ×¼dçÙº7û¼tÄ×ü7ØÙÕ`ÚLÜÝÔÉßÃrâãhä`¼Æýº»ÖÁÕrÕ`¼7çÙçÙØÙÕÁÚ Â庱ÚÉÕÁ¼t»|Ôļ7×ØÙ×|»ºÕræT¼dĺ±»ØÔ:·¹ë,êLþpÊÔã)ÿ ò^º×ãhÔÉÖÁÕÁ½ï ö ÕæTÔÉÂÀrº±ÄØÙ×|ÔÉÕÆ`ºë,êFþ Ôã7Å<ï òݺ×SãhÔÉÖÁÕÁ½¥ØÙÕ º×|¼7æTÔÉÕÁ½×ºÂÀrç¼pò,Ø»Û ºÀrØÙÕrÕ`¼7½¥Ü^Ô õ ä`¼ õ ¼7ç¼7æT»|ÄÔY½`¼WºÕÁ½º×|¼7ÕÁ×¼\ÜÝÔÉßÃrâ,ã¹ä`¼W¼7ç¼7æT»|ÄÔ<½`¼ïë)ÛÁØÙ×Sç¼7º½r×^»|ÔdºçÔfòC×|ÀrØÙÕYè¢ÀÔÉçÙº±ÄØ7º±»ØÔÉÕøÔ㺱ÃÔÉÖ`»7ÿ5ã?ÔÄÜ^ÔÉß,Ãrâã¹ä`¼º±»ÄÔ<ÔÉ »|¼7ÂÀ¼tĺ±»Ö`ļïâØÚÉÛYè¢Ä¼7×|ÔÉçúÖ`»ØÔÉÕF»|ĺÕÁ×ÂåØú××ØÔÉÕF¼7ç¼7æT»|ÄÔÉÕóÂdØÙæTÄÔÉ×æTÔÀ<û²·¹âþ,ðÝêZÊØúÂ庱ڼ7×W×Û`Ôò»ÛÁº±»ò,ÛÁØúç¼»ÛÁ¼üÁÄ×|»×ºÂåÀrç¼ÛÁº×º¥ã¹ÖÁçÙçûFºÂÔÄÀrÛ`ÔÉÖr×W×|¼7ÕÁ×|¼åçÙºfû¼tÄ7Æ »ÛÁ¼å×|¼7ÕÁ×|¼åçÙºfû¼tÄØÙÕx»ÛÁ¼å×|¼7æTÔÉÕÁ½ó׺ÂåÀrç¼ØÙ×çÙº±ÄÚ¼7çÙû:ºÂÔÄÀrÛ`ÔÉÖÁ×ò,ØÙ»Û³ÕÁºÕ`Ô±èjæTÄûY×|»ºçÙçÙØúÕ`¼ØÙÕÁætçÙÖÁ×ØÔÉÕÁ×tï ÝÔ»ÛQÀrØÙÕrÕ`¼7½²çÙº7û¼tÄ×øº±Ä¼ãhÔÉÖÁÕÁ½³»|ÔóüÛÁØÚÉÛrçû»|¼TñY»Ö`ļ7½ùºÕÁ½LæTÄû<×»ºçÙçÙØÙÕ`¼ïëýÔ ×»ÖÁ½`û×|ò,Ø»æÛÁØÙÕ`Úø½ÁØÙ×|»|ÄØÙÃrÖ`»ØÔÉÕÁ×7ÆYçúº±ÄÚ¼\êFë,ì º±Äĺfû<×òݼtļÀrº±»|»|¼tÄÕ`¼7½xÖÁ×ØÙÕ`Ú¼7çÙ¼7æT»|ÄÔÉÕYè¢Ã¼7ºÂ çÙØ»Û`ÔÚ±è

ĺ±ÀrÛûºÕÁ½»Û`¼\Â庱ÚÉÕ`¼t»|Ô±è¢ÔÀÁ»Øúæ¼tÄļH¼7æT»·êðÝÊSòݺ×ÖÁ×|¼7½L»|Ôø¼7º×ÖÁļ»Û`¼×ò,Ø»æÛrØÙÕ`ÚÔãN»Û`¼×¼7ÕÁ×|¼çÙºfû¼tÄ7ïêðQļ7×ÖÁç»×^ãhÔÄ,»Û`¼W»lòÔ ×ºÂÀrçÙ¼7×Sº±Ä¼æTÔÉÂÀrº±Ä¼7½ùØÙÕº±Äĺfû<×,ò,ػ۽`¼tôYØÙæT¼7×SÔãN½ÁØH¼tļ7Õ»)×Øt¼7×7ï

! #"%$'&)('*,+-/.102-/. 3546 +-/.102-. 7461098. :<;!. 35=26102-/.02;/. 3?>

@'A,BC$D=EF&HG<>I=J<44/&F$D(F('*KMLONMPQRSQTR!L<U2KMLVORXWYHZO[TK

\

]¡_AD _T@/VH=h>AXYDa X<¡L9¹9<DOY¯EF9<OY;H_TX<DA>=h>_t9<;_³=?; EZ9OY;_A=hQ_TM;H;M;_A=hXY;H> 8 P >"!# \$ GÁ_A@a¥@9Y%ý;'&DAX(& XY>VF¡¢X<DSM>A9<>)>_AXYDT9OYhEF;`_T>)=h;ùEF9<OY;f_T=hDT9<;VHXYE 9<>>ELELXYDa 8*)]8+!,#.-G0/ $ RPXxXYE'&ýf_T1=?_T@Í2=h>_T=?;OF_At@;X3hXYOY=?>GU8*)]8 E¥M>_=h;HXYD4&ýXYDA9_TV=?>51=?_A@Í>=76>8 9:-(;=<UE 9<;V+?>>R]p_\>Mt@³>AEF93>NV=hEL;>=hXY;H>G_T@øEZ9OY;_A=hå>41=ú_Tt@=?;O% f£@9r=hXYMHDX<¡9;Z=h;HV=>r=hVHM93V=?=?>=?; ?M;V@&DA=?EZ9DA=7úaA%`aL=?_A>OYXYEL_TDa'%MH_W9Bh>AXC%`aL_A@OYDA9<=h;>_ADAMf_TMD\X<¡_T@EZ9<O<;_A=hD¹9±aYDA>RFE|;&9<D_T=?MGh9<DGr9C& X(úaDar>_T937?=h;W>;>¹9±a<D,EZ9±a=h9<VF_AX >=hO£;=IH±9<;`_<9DA=¹9_T=hX<; =?;:>J1=?_Tt@H=h;Oxt@9<DT9<f_TDA=h>_T=?>1@H;K¹9DAOYå;ÁMEA% D>X<¡SVr=h>9<Dø¡j93%D=h9_TV=h;²9<;«8*)]8 9<DADA9±aL#NM $ RE$_@9<>% ;K&DAX(& XY>V³_T@9__T@ M>AX<¡,9EFXYD4&@XYMH>EZ9_TD=¹93?>¡¢X<D_T@H>A;>A5¹9±aYD=?;x9<;x8ÍP XYD,9ø>4&=h;£O93><=?E&DXY>)_T@H\M;=ú¡¢XYDAEL=?_|a X<¡N>J1=?_Tt@H=h;Oø=h;Z8*)]8P#NMGQ; $ RPW@=?>&93&ýDWV=h>M>>A>_T@HdMH>AdX<¡ÝX<;å>AMt@ÍEZ9_AD=¹93lGH[X(R%TS¡VU-<G9<>W_T@å>;>¹9±a<DR

WYXAZDWYC\[]WY

BH9<E'&G?>1DAªV^&ýXY>=?_AVL%`aVHxEZ9OY;_ADAXY;>_&MH__TDA=h;HO²=h; 9²BQ&MH__TDV`UÝ=>hEL>,E|;H<RQB@9<Eù£DAXra V& XY>A=ú_T=?XY;:>a>_TEÍRåPW@ _AM;;^b%9<DDA=?D\X¡)]5 ÷c5d 1p9<>¡¢X<DAELV+%`ae&G¹9<>EZ9LX2H=?V9_A=hXY;²X¡,9>_&HMH_A_AD£$V& XY>=?_TVF]QHT?EÍR c ;>Af_)X<¡ >T9<E'&Gh>b1p9>F&9_A_AD;V=1=?_A@h_ADAXY;£f%ý9<Eg?=?_A@XYOYDA93&@`a_TXF¡¢XYDAE X<;Á_T9<_AVK%=ú_T>¡¢XYD\^hf_TD=h±9B_A>_A=h;Ox9<;V²EF9<OY;f_TXYD>=h>_T9<; EL±9<>MDAEF;Á_A>Rh=?>X<¡DAf_t9<;HOYMG¹9D,>@93& <G9<>_& f_DA9_T=?XC-d9<;HVF>=76>VHXi1;L_TXC8 9.j,<UElk=8 9./<UEg1DA¡j93%D=h±9_TVR^]\;£X<_A@D>A_X<¡>T9E&G?>m1p9>p>A^&9<DT9_Túa'&9_A_AD;VZ_AX ¡¢XYDE V;>9<DDT9±ar>pX<¡NVr=h>pX<¡NDf_t9<;O<MG¹9<D9<;V ^7?=7&H_A=h±9B^>A@9B&ý>A1=?_T@9; 9<>_& f_DT9_T=hX:X<¡-Q9:;:9<;V >=76>¥VX1; _TXn-3-(;;EokLp(8<;E R²PW@=?>>Af_1p9>¥M>AV ¡¢XYD¥X(%>DJ=?;O³EF9<OY;f_T=hL>41=ú_Tt@=?;OK% @9r=hXYMHD¥X<¡W_T@Hª>A;H>A@¹9±a<D¥M>=h;O«8 c qEL±9<>MDAEF;Á_A>RS5)q8r19<>& D¡¢X<DAELV³XY;Q9x>_dX<¡F1=?_A;>>å>T9<E'&Gh>\_TXª>_TMVa:_T@HE¥MG?_A=7h9a<D>_ADAMf_TMDø=?;óV_T9<=7lR

E|;²_T@H=h>5&93&ýDGUV9_t9Z¡¢DXYE _s1Xª>T9E&G?>9DAA&D>;`_TVutåBH9<E'&G? \ Gv1=?_T@³P9@/xw)My-(wª8Í; E|Dz R:;(w²[XxR%TS¡VU/xw ]5 ÷cd -3w³[XxR%TS¡VU;(wÍP9n;G)9<;V"B9<E& h@-rGb1=?_T@ P9K/xw*)M`-(w³8Í; E|Dz R:;(w [XxU|-(wª]5 ÷c5d -3w:[XxR%TS¡VU;(wóP9e; 1@HDAL_T@=?aÁ;>>A>¥9<DAL=h;«;E!fRZPW@ÁM>GÝ_T@HL_s1X>T9E&G?>VH=>ýDXY; ?aÍ=h;:_A@EZ9_TD=¹93M>VQ¡¢XYD\_A@&=h;H;VKh9a<DR¥[XxR%TS¡VU@9>9xEFX<EF;Á_X<¡ ;38¥E¥M~YG^hXY>_TXù DAEF937?Xa R=I U- ÷ !fG9;Vó@9<>9@=hO<@ª;XYMHOY@R% 9<;VeS¡X<;Á_A;`__TX% 9<ELXYD_&H@XYM>W=?;x_T@=?;HGhE ¡¢X<DAE R^PW@å>A;>AC¹9±aYDA>9<DA\2Q&ý_TVÍ_AX'% YDaª>=hEL=7¹9D=?; >_TDM_AMDAG% =h;HOø9EFXYD4&@XYMH>bHThEL>SV& XY>=?_TVFX<;Z9<ELXYD4&@XYM>)9BhMEL=h;9RSX1YDG9<>)V=?>AM>A>V|% ?Xi1åGY_A@a

-

9<Då¡¢X<M;Vª_TX=% dVH=>ýDA;`_±R

^ CWT G' T

UÝ=?OR \ >A@X1>X(%H>ADJYV])p£ S hXrX(&>å¡¢XYD D_T9<;OYM ¹9<DM;_A=hXY;H>¥X<¡ \ 9:;38*<UEok 8 9 z ;e<UE'>A=>6<RPW@xP8e) ¡¢XYD¥BH9<E'&Gh \ =h>CMR:p'9;V/¡¢XYDB9<E& h-Í=h> \ jHR MxR >=h;O:_A@<MG>h=fDAùVH;=ú_T=hX<;¡¢XYDå>_&H=h;y&ýX(h9<DA=>6±9_A=hXY;`# j $ G_A@>FP8e) 93?M>d>AMHOYOY>_¥9ó>_&H=h; & X(h9<DA=>6±9_A=hXY;²X¡W9<DXYM;V \ ; ¡¢XYD[XxR%TS¡VUx9_ DXXYE _TE'& DT9_TMD<RóPW@Z\2t@9<;OY%=¹9<>d=h;BH9<E'&G? \ 1=?_T@/[XxR%GS¡VU&H=h;;V¹9±a<D=h>-(-3; c å9<;HVÍ=?;:B9<E& h-A1=?_A@:[X(U-&H=h;;Veh9±aYD=?>D/x;38 c <R

E|;AU=hORi-9<D &D>;`_TV=S5)q8 =hEF9<OY>NX¡H_T@H_s1X\>T9E&G?>R^BMHD_&D=h>A=?;O(úaYGi%ýX_T@&H=h;;Vh9a<D>9<D¡¢XYM;Vª_TX=% &DAVXYEL=h;9<;`__?aFDar>_t93>h=h;H9<;V @=?OY@G?aL_T\2r_TMDVUR)PW@dDa>_t93>h=?;\>_TDAMH_TMHDAdX<¡_T@H¥[XxR%TS¡VUC&=h;;HV*h9±aYD2Q&Gh9<=h;H>_A@øX3%>AD49_T=?XY;:X¡^2t@9;OYA%=h9<>=h;:BH9<E'&Gh \ RDhMHd_AX_T\2r_TMD93hD±9<VaÍ>_T93%Gh=?>A@V+%`aÍ_A@¥M;HVD4?ar=h;Oª8Í;GE|DG _T@[XxR%TS¡VU¹9±a<DVXr>;X<_\>AE _AXOYDXi1#9<ELXYD_&@HXYM>GÁ9B?_T@HXYMOY@ù>AX<EFW>EZ93>9<ELXYD_&H@XYM>SDOY=?XY;>)9<D>_T=>7HX3%>AD4YV U=hOR(- 9x!4!fRPW@VOYDApX<¡_T\2r_TMDp=h;d_T@ &=h;;HVL[XxU h9±aYD=h;¥BH9<E'&Gh -=h>@=?OY@DR E|;A?XX3ar=?;O9_Ý_A@>;>¹9±aYDX<¡B9<E& h \ GS9ó¡¢MG7úaQ9<ELXYD_&@HXYM> [XxR%TS¡VU¹9±a<D =?>øX3%>AD4YVUR+SX1YDGS_T@F>A;H>A|h9a<DøX<¡BH9<E'&G?-å=h>¡¢X<M;VZ_AX @9Y9 >A=?OY;=>H±9<;`_ &DAX(& XYD_T=hX<;ZX<¡NDar>_T937?=h;DAOY=hX<;>R^PW@H=h>=?>MH;2Q& _AV9<>% X<_T@Q_T@L>A;>A¹9±aYDA>d9<DLO<DAX1;XY;¯9<ELXYD_&H@XYM>d93?MEF=?;9HR¥PW@HZ93?MEL=h;9|%9DADA=?DVXr>d;X<_>AE _TXª¡¢MG>?a*%DA93a²_T@ù_T\2r_TMDF>_t9B%Gh=?>A@V %`a³_T@H% X<_A_AXYE ^h_TDXVHh9a<D>ø9;V>XYEFùX<¡=?_&DX(&9<O`9_T>=?;Á_AX_T@_TX3& ^h_TDXVH<R

E|;:_ADar=h;OF_TXªM;VHDA>_t9<;HVQ_A@¥V=IDA;>%ýf_s1;³_T@ø_s1Xó>A;>Ah9±aYD>G 1&D&9<DVKh9<DAOY9<DDT9±ar>x_TXXYE'&9<D+%`a 8 c q EL±9<>MDAEF;`_T>R PXOYf_ 9<&H_T93%Gh³>_t9_A=h>_T=h93\VH=h>_ADA=>%MH_T=?XY;>X<¡>J1=?_Tt@H=h;OGSX<;xDAÁM=hD>¥=?V;`_T=?±93,V=?>=h;_A@x;`_A=hDAx9<DADA9a<R²]\; =?E& XYD_t9<;`_øOYX`93,X<¡W_T@H&9__TDA;=?;O|&DX>A>19<>\_AX|a<&Q>A@93&ý>å9<;V³>=76>X<¡,93>V^r=h>=?;³9<;³9<DDT9±aÍ>A=hEL=7h9<DRh=?>1DAF>_&9V«¡j9<Dd93&9<D_å_TX%ýù;XY;r£|=h;`_ADT9_T=?;OR'UÝ=?OR /ó>A@X1>¥9ó>A9<;;=?;O h_ADAXY;«EF=?DXY>AX(&ý BQq8*!W=?EZ9OYX<¡Ý9ù_|a &=?±93N8 c ,q9<DADA9axX<¡Ý^7?=7&>>R

)&D>A;`_t9_A=>Y8ó£ SlhXrX(&>W¡¢XYDDA_t9;O(h>\EL±9<>MDAV+%`a:8 c ,q9<D 9Bh>AX'&G?X<_A_AV:=?;+UÝ=?OR \ R] ¡¢±9_AMDAWr=hV;Á_=h>^_A@>_A&G& VL_TDT9;>A=ú_T=hX<;=h;ùXY;WX<¡ý_T@VOY>R^PW@=?>m19<>)¡¢DArMH;`_"úaX(%>D4<V=h; ^h_TD=h939<;V 8 c q V9_t9/¡¢DAX<E D_T9<;OYM ¹9<D@%=ú_T>G%M_ó;X<_ó=h; ^7?=7&>>R PW@Q>_A&> 9<Dh=>a<^?aÍDAh9_TV³_TXx¡¢XYDEZ9_A=hXY;:X<¡ <XYD_A=h>å9<;VQX<_A@Då_T>_A@9_d9<Dar;HXi1;Q_TX 9Býf_d>41=?_At@=h;HO=h;óD_T9<;O(?>ELXYDA\_A@9<; =h;ó>h=>&>A>,# z G B$ R

E|;UÝ=hOHRQML9<D&GhX_A_TVÍ8 c ,q"V9_T9 ¡¢XYDW>h=7&H>A>R^]\>W\2Q&ý_TVUG-XrD=>r=ú_|ax=h;HDA9<>A>>AMG%>_t9<;r£

/

_T=h937úaó9<>%H=?_>=76¥VDA9<>A> ¡RUÝ=?OR0; 9x!4!fRPY1XóV=>ýD;>2=?>_% _s1;/BH9E&G?> \ 9<;Vy-RUÝ=?DA>_G_T@å=?;D±9<>ø=?;ÍXDA=Ir=?_|aª=?>>EZ9B7hD¡¢XYDBH9<E'&G?,-RpBrX<;VUGý9L>=hOY;=IH±9;Á__T9<=7U=?>>A;:=?;BH9<E'&G?A-x9_\>AEF937>=76>9<;V³X<;G?a =h;Í_TDT9;>A=ú_T=hX<;>¡¢DXYE &9<DT9B7h^N_TXª9<;`_A=7&9<DA937?lR]>=h;HV=>r=hVHM93%=ú_T>=h;ø_A@p9DADT9±aå>J1=?_Tt@ù9_Ý>4h=hO<@Á__?aVH=>ýDA;`_ÝXDA=Ir=?_T=?>G_A@>4hX(& ~ OY=><>_T@>41=?_At@=h;HOV=?>_TD=7%M_T=hX<;1=?_A@x>_T9<;V9DAVóV^r=h9_T=?XY; ¡¢XYDp9å9<M>>A=¹9;H_\!7RSPW@_t9=7-=h;óB9<E& h- 9<M>>p_T@H;XYDEZ9Bh=76VÍXrDA=>r=?_|a:>_&D±9<VG ~ TGU_TXª=?;D±9<>¥¡¢XYD\X<;X<¡)_T@VOY> >A'UÝ=hOR ; %!_!7R Br=h;_T@H,&HDA=hEF9<DaZV=IDA;,%ýf_s1;:_A@_s1XL>T9E&G?>W=?>p_T@dDa>_t93>h=?;=?_|aLX<¡_T@å>A;>A,¹9±a<DG_A@>_s1XªV=>ýD;>>AMHOYOY>_d9h=?;Ga%ýf_s1;³_T\2r_TMDù9<;V³>41=ú_Tt@=?;OªV=?>_TD=7%M_T=hX<;UR]VV=ú_T=hX<;93XY;£_TD=7%M_T=h;HO¡j9<_AXYDA>)X<MGhV=% _A@=h; ?M;X¡ý_A@V=>ýD;`_ &=h;;HV'¹9±aYDA>)VM_TXhXr±9BHV=?>_& DA>=hXY;H>=h;&=?;;Veh9a<DWXYD=h;Á_T9_T=?XY;>9<;HV VH=>ýDA;`_&H=h;;=?;OAH^hV >_TD;O_T@># p $ R

| , G

E|; >MELEZ9<DaYGÉ_TM;H;>h=h;HOWEZ9<O<;_AXYDA>A=h>_t9<;H,@9<> %ý;¥X(%H>ADJYV=h;YM;_A=hXY;H> 1=ú_T@ [XxR%TS¡VU?f_TDAXrV>GL93?_A@XYMO<@ X(%H>ADJYV P8*)P<9BhM>«>MOYOY>_/9 ?Xi1 >_&=?;g& X(¹9DA=769_T=?XY; X<¡ \ ; ¡¢XYD[XxR%TS¡VU<Rq 2t@9<;O<@%=¹9<>19<> X(%H>ADJYV/¡¢XYD¥8 ;GE|D\wY[XxR%TS¡VU¹9±aYDA>RS)q,8 =?EZ9<O<>dXY;£HDEFV¯_T@9_d>AMt@[X(R%TS¡VU-'&=?;;V ¹9±aYDA>1DAF;X<_ 9<EFX<D_&@X<M>%MH_C¹9<DOYúa²Dar>_t9B7h=?;<RE|;X<E&9DA=h;HO*S)q,8 =?EZ9<O<>åX<¡p_s1X²>T9E&G?>1=?_A@V=IDA;`_&=h;;HV h9a<D>G^=ú_,19<>¥^h9<D_úa³>A;_T@9_^_T@HW>_TDM_AMDAX<¡-_A@W9<ELXYD_&H@XYM>^EF9_ADA=h93r=h>^=?; ?M;V'%`a¥_A@pM;HVD4?ar=h;Oh9±aYD>)9<;V_T@H=hD_T\2r_TMD<RYh^&ý;V=?;OùMG&ýX<;Í=ú_T>D&ýX<>A=?_A=hXY;ª=?;ª_T@åP8*)5E¥MGú_T=>¹9±aYDp>_T9<a-G-_A@d>T9<ELEZ9_TD=¹93EZ9±a% 9<ELXYD_&H@XYM>,XYDDar>_T937?=h;W_AXC9<Dar=?;O VOYDA>R,PW@H9<ELXYD_&@HXYM>93hMEL=h;9%9<DAD=hD93&G&9<DA;Á__?aVXr>F;X<_L¡¢MG7úa %DA93a _T@ _T2r_AMDA²>_T93%Gh=?>A@V]%`aCM;VD_?ar=?;O h9a<D>R@; &9_A_TDA;V#=h;`_AX8*)]8 9<DADA9±a>GN_T@_s1XÍ>A9<E& h>>@X1VV=IDA;Á_å>J1=?_At@=h;O% @9r=hXYMHDR¥PW@ù>J1=?_Tt@H=h;O@19<>>A=?EF=>¹9<D9_åV=?EF;>A=?XY;>å93% XY;38(8;Eo%M_ø=?;D±9<>=h;O3?aÍV=>ýD;`_ø9_åV=hEL;H>A=hX<;>% hX1 -38(8<;EªRPW@=?>Ý>AMHOYOY>_T>^_A@9_Ý_A@pVOYDApX<¡-Dar>_T937?=h;=ú_|aX<¡_T@Hp>A;>Ah9a<DÝ9B_A>Ý_T@EZ9<O<;_A=h,>41=?_At@=h;HOX<¡%=?_A>R

! "#%$'&

PW@9MH_T@X<DA>51XYMG?V+h=>a<ø_AXZ_T@9<;Ga:8Í=ht@^7? 9<;O(% XYDA;²¡¢X<D\@DOYDA9_@H7&e1=?_T@Í_T@ù8 c qEL±9<>MDAEF;Á_A>R

M

I ìÁïrêùÔ<Ô<½Á¼tĺYÆï ØÙÕÁ½`¼tÄ7Æ`ºÕÁ½Fì`ïÁßÔfò^ºXÆì`ïÀÁÀrçïÛûY×tïrÆÿÿÇÇL·) Êï Ç Ó ïWºçÙçÙº±ÚÉÛ`¼tÄ7Æ¿HïUº±Ä YØÙÕÆïýÖÆ\ï ^ØÙºÕÆïWêLº±Äç¼tûÆþïç»ÂåºÕÆ\¿ïþ,Øú×Û»|ÔÉÕ-Æïþ,Ô<æÛ`¼Æ

ÜïrìºÛÁÕ`¼7×tÆÁëï¿YÛÁº7òÆ`¼t»,ºçïÆìÁï,ÀÁÀçïÛû<×tïÁÆ< ø·) Ê勵Hïëý¼7Û`ĺÕÁØÆì`ï-¿YçÙºÖ`ÚÉÛ»|¼tÄ7Æð)ï-Ü^Û`¼7Õ-Æê ï¸ÖÁÄçÙºÂÆì`ï-¿YÛÁØÆHºÕÁ½ªêó︼7â¼tÄļ7ÕÆ ö ððð ëýĺÕÁ×7ïHêFº±ÚÉÕï

"! ·) ÉÊï #øâï ºÕ`Ô`Æ ï ݼ7××ÛÁÔ`ÆïâØÙÚÔ`Æ åï pÛÃrºYÆêóïâº×ÛÁØÙÂÔ»|Ô`ÆëWïêLØ 7Ö`ÚÉÖÁæÛrØÆHºÕr½Zê ïHâÔÉ×|ÔÉÂåØ¢Æ ö ððð

ëýĺÕÁ×tïrêFº±ÚÉÕï ͷDZÈÈÉÇÉÊï ÿø¸\ï Ó ºÕ`Ú`Æ"$Uï%pØÙºÕÆ`ì`ïÁ¸pºÖ`ÚÉÛ»|ÔÉÕÆHÜïÁßÔĽÁÂdºÕÆÁêóïÁëýÔÉÕÁ½`ĺYÆÁ¸\ïÁþ,¼t¼7½ÆÁºÕÁ½¸\ï ÝÄÔfò,ÕÁ¼7çÙçÆÁì`ïÀÁÀrçï

ÛûY×tï&-ÆűÿZ·Ç±ÈÈfÊï Å ê ïìÉÖrçÙçÙØ('¼tļÆÛûY×tï-¼t»|»tï !) ÆÇÇÿF·) ±ÿÉÊï*+øëWï¿`æÛ`ļ-, Ærì`ïÁäUØÙ½Áç¼tÄfÆMåï ØÄ HÆÁºÕÁ½ùì`ïÜ^ÛÁº±ÀrÂåºÕ-Æ`ìÁïrêLº±ÚÉÕ-ïHêFº±ÚÉÕïêFº±»|¼tÄ7ï./ ! Æ L·) Êï0øþïÔɼ9ÆïUºXHÆ1ï ÖÁÖÆï ØÄ HÆ`ºÕÁ½ùì`ïHÜSÛÁº±ÀrÂåºÕÆÁìÁï,ÀÁÀçïÛû<×tï" ! ÆHÅM7ÅL·) ÉÊï ¥Üï7ë,ØÙÖÁ׺ÕÆëWï7¸pØÙÂÔÀÔÉÖÁçÔÉ×7Æ<ï<pÖrÕÁº½é|¼7çÙºYÆê ïfâ¼7ÛÁÕƱâï7ô±ºÕ½`¼7Õ¼tÄÚ`Æ21\ïf½ÁºÜÝÔÉ×|»ºYƺÕÁ½ïfâ¼7Õ`ÄûÆ

ÛûY×tïÁþ)¼tôHï 43ÁÆÿ0±ÈL·Ç±ÈÈÈÊï

;

ä ö ï,±¾ÜÝÔÉÂÀrº±ÄØú×|ÔÉÕ Ôã ¼7ç¼7æT»|ÄØúætºçþSèjâ"½rº±»ºù·¹×|ÔÉçÙØÙ½¥çÙØÙÕÁ¼ÊNò,ØÙ»Û êðQçÙÔÔÀr×W·¹½Áº×Û`¼7½çÙØÙÕ`¼ÊãhÔÄÝļ7æT»ºÕYèÚÉÖÁçÙº±Ä,ÃrØ»×tïêFº±ÚÉÕÁØ»ÖÁ½`¼WÔãêð¯×ØÚÉÕÁºçºçÔÉÕÁÚûèjºñ`ØÙ×)ØÙ×)ÔÉÕÁçûdļ7çÙº±»Øô¼ï

ä ö ï`Ç<¾âþðê ØÙÂdº±Ú¼7×^ÔãÝ·¹ºÊS¿YºÂÀç¼ ò,Ø»ÛÜÝÔÉßÃrâãhä`¼WÀØÙÕÁÕ`¼7½øçÙº7û¼tÄ7ÆÁºÕr½x·hÃÊ¿YºÂåÀrç¼WÇòػۥÜ^ÔÉä`¼ÀrØÙÕrÕ`¼7½¥çÙº7û¼tÄ7ï ö Õ ·hÃÊÆrºæTÄûY×|»ºçÙçÙØÙÕÁ¼Ä¼tÚÉØÔÉÕùØÙÕ¥»Û`¼×|¼7ÕÁ×|¼çÙºfû¼tÄØÙ×SætØÙÄætç¼7½ï

ä ö ï <¾¿Yðê ØÙÂ庱ڼ)Ôãºêðͺ±Äĺfû\òØ»Û ÉÈÈÕÁ DZÈÈÕÁÂ#¼7çúçÙØÀr×|¼7×Nº±»ºWÀrØ»æÛÔã0±ÈÈÕÁ ÉÈÈÕÁÂÀrº±»|»|¼tÄÕÁ¼7½Ãû¥¼7ç¼7æT»|ÄÔÉÕYè¢Ã¼7ºÂ2çÙØ»Û`ÔÚĺ±ÀrÛûï

ä ö ï`¾ê ðQçÔ<ÔÀr×Ýã?ÔÄ,¼7çÙçÙØÀÁ»ØúætºçÁÃrØ»×^òػۥº×|À¼7æT»Sĺ±»ØÔÔãÇ ÿ<ï^êLØúÕ`ÔÄSºñYØÙ×S½rØÙ¼7ÕÁ×ØÙÔÉÕøØÙ×SØúÕÁ½ÁØÙætº±»|¼7½ãhÔÄ,½`¼tôYØÙæT¼7×tï

ä ö ï`ÿ<¾ð ¼7æT»ÝÔã½`¼tôYØÙæT¼W×Øt¼ÔÉÕ󷹺ÊÝæTÔ¼tÄætØÙô<Ø»lûÆ Æ`ºÕÁ½ª·hÃHÊÕ`ÔÄÂåºçÙØ t¼7½øæTÔ<¼tÄætØôYØ»jû ×|ÀÁļ7º½-Æ Æ`ãhÔļ7çÙçÙØÙÀÁ»ØÙætºçHÃrØ»×tï ö Õ ·hÃHÊÆÁ»ÛÁ¼W»jòÝÔ êùèjâçÙÔÔÀù¼7½ÁÚ¼7×,º±Ä¼WÀrçÙÔ»|»|¼7½ù×|¼tÀrº±Äº±»|¼7çÙûï

j

3.8e6

3.85e6

3.9e6

3.95e6

4e6

R (

MΩ

)

-100 -50 0 50 100H (Oe)

2.2e6

2.3e6

2.4e6

2.5e6

2.6e6

2.7e6

R (

MΩ

)

Sample 1

Sample 2

z

p

125nm600nm

-400 -200 0 200 400H (Oe)

600nm125nm

Sample 1

Sample 2

\ 8

0 100 200 300 400 500 600size (nm)

50

100

150

200

Hc

(Oe)

Sample 1Sample 2

(a)

0 100 200 300 400 500 600size (nm)

0

0.1

0.2

0.3

0.4

0.5

σ/H

c

Sample 1, ap → pSample 1, p → apSample 2, ap → pSample 2, p → apFit to ΟFit to ∆

(b)

\M\