On the nature of asymmetry of nucleation centers activity in ultrathin Co films and Co/Pt multilayers
Magnetization reversal in ultrathin Pt(10 nm)/Co(0.6 nm)/Pt(3 nm) magnetic films and Pt(10 nm)/[Co(d)/Pt(1 nm)]n/ Pt(2 nm) (d = 0.4, 0.6, 0.8 nm, n = 2, 4) multilayers with perpendicular anisotropy has been studied using Kerr microscopy. These materials demonstrate unusual effects of activity asymme...
Збережено в:
Дата: | 2008 |
---|---|
Автори: | , , , , , , |
Формат: | Стаття |
Мова: | English |
Опубліковано: |
НТК «Інститут монокристалів» НАН України
2008
|
Назва видання: | Functional Materials |
Теми: | |
Онлайн доступ: | http://dspace.nbuv.gov.ua/handle/123456789/137227 |
Теги: |
Додати тег
Немає тегів, Будьте першим, хто поставить тег для цього запису!
|
Назва журналу: | Digital Library of Periodicals of National Academy of Sciences of Ukraine |
Цитувати: | On the nature of asymmetry of nucleation centers activity in ultrathin Co films and Co/Pt multilayers / Yu.L. Iunin, Yu.P. Kabanov, V.I. Nikitenko, X.M. Cheng, A.J. Shapiro, C.L. Chien, R.D. Shull // Functional Materials. — 2008. — Т. 15, № 1. — С. 51-55. — Бібліогр.: 12 назв. — англ. |
Репозитарії
Digital Library of Periodicals of National Academy of Sciences of Ukraineid |
irk-123456789-137227 |
---|---|
record_format |
dspace |
spelling |
irk-123456789-1372272018-06-18T03:06:53Z On the nature of asymmetry of nucleation centers activity in ultrathin Co films and Co/Pt multilayers Iunin, Yu.L. Kabanov, Yu.P. Nikitenko, V.I. X.M. Cheng Shapiro, A.J. C.L. Chien Shull, R.D. Characterization and properties Magnetization reversal in ultrathin Pt(10 nm)/Co(0.6 nm)/Pt(3 nm) magnetic films and Pt(10 nm)/[Co(d)/Pt(1 nm)]n/ Pt(2 nm) (d = 0.4, 0.6, 0.8 nm, n = 2, 4) multilayers with perpendicular anisotropy has been studied using Kerr microscopy. These materials demonstrate unusual effects of activity asymmetry of nucleation centers and domain wall motion. The field dependences of these effects have been studied and the asymmetry of the domain wall nucleation has been found to be suppressed by application of a magnetic field much stronger than the sample coercivity. The asymmetry comes back after several reversals at a lower field magnitude. The asymmetry of domain wall velocity decreases abruptly and vanishes as the reversal field increases in low coercivity ultrathin Co films. The effect recovers as in the reversal field value decreases. A role of the Co/Pt interface defects and nonlinear spin excitations in these phenomena is discussed. 2008 Article On the nature of asymmetry of nucleation centers activity in ultrathin Co films and Co/Pt multilayers / Yu.L. Iunin, Yu.P. Kabanov, V.I. Nikitenko, X.M. Cheng, A.J. Shapiro, C.L. Chien, R.D. Shull // Functional Materials. — 2008. — Т. 15, № 1. — С. 51-55. — Бібліогр.: 12 назв. — англ. 1027-5495 http://dspace.nbuv.gov.ua/handle/123456789/137227 en Functional Materials НТК «Інститут монокристалів» НАН України |
institution |
Digital Library of Periodicals of National Academy of Sciences of Ukraine |
collection |
DSpace DC |
language |
English |
topic |
Characterization and properties Characterization and properties |
spellingShingle |
Characterization and properties Characterization and properties Iunin, Yu.L. Kabanov, Yu.P. Nikitenko, V.I. X.M. Cheng Shapiro, A.J. C.L. Chien Shull, R.D. On the nature of asymmetry of nucleation centers activity in ultrathin Co films and Co/Pt multilayers Functional Materials |
description |
Magnetization reversal in ultrathin Pt(10 nm)/Co(0.6 nm)/Pt(3 nm) magnetic films and Pt(10 nm)/[Co(d)/Pt(1 nm)]n/ Pt(2 nm) (d = 0.4, 0.6, 0.8 nm, n = 2, 4) multilayers with perpendicular anisotropy has been studied using Kerr microscopy. These materials demonstrate unusual effects of activity asymmetry of nucleation centers and domain wall motion. The field dependences of these effects have been studied and the asymmetry of the domain wall nucleation has been found to be suppressed by application of a magnetic field much stronger than the sample coercivity. The asymmetry comes back after several reversals at a lower field magnitude. The asymmetry of domain wall velocity decreases abruptly and vanishes as the reversal field increases in low coercivity ultrathin Co films. The effect recovers as in the reversal field value decreases. A role of the Co/Pt interface defects and nonlinear spin excitations in these phenomena is discussed. |
format |
Article |
author |
Iunin, Yu.L. Kabanov, Yu.P. Nikitenko, V.I. X.M. Cheng Shapiro, A.J. C.L. Chien Shull, R.D. |
author_facet |
Iunin, Yu.L. Kabanov, Yu.P. Nikitenko, V.I. X.M. Cheng Shapiro, A.J. C.L. Chien Shull, R.D. |
author_sort |
Iunin, Yu.L. |
title |
On the nature of asymmetry of nucleation centers activity in ultrathin Co films and Co/Pt multilayers |
title_short |
On the nature of asymmetry of nucleation centers activity in ultrathin Co films and Co/Pt multilayers |
title_full |
On the nature of asymmetry of nucleation centers activity in ultrathin Co films and Co/Pt multilayers |
title_fullStr |
On the nature of asymmetry of nucleation centers activity in ultrathin Co films and Co/Pt multilayers |
title_full_unstemmed |
On the nature of asymmetry of nucleation centers activity in ultrathin Co films and Co/Pt multilayers |
title_sort |
on the nature of asymmetry of nucleation centers activity in ultrathin co films and co/pt multilayers |
publisher |
НТК «Інститут монокристалів» НАН України |
publishDate |
2008 |
topic_facet |
Characterization and properties |
url |
http://dspace.nbuv.gov.ua/handle/123456789/137227 |
citation_txt |
On the nature of asymmetry of nucleation centers activity in ultrathin Co films and Co/Pt multilayers / Yu.L. Iunin, Yu.P. Kabanov, V.I. Nikitenko, X.M. Cheng, A.J. Shapiro, C.L. Chien, R.D. Shull // Functional Materials. — 2008. — Т. 15, № 1. — С. 51-55. — Бібліогр.: 12 назв. — англ. |
series |
Functional Materials |
work_keys_str_mv |
AT iuninyul onthenatureofasymmetryofnucleationcentersactivityinultrathincofilmsandcoptmultilayers AT kabanovyup onthenatureofasymmetryofnucleationcentersactivityinultrathincofilmsandcoptmultilayers AT nikitenkovi onthenatureofasymmetryofnucleationcentersactivityinultrathincofilmsandcoptmultilayers AT xmcheng onthenatureofasymmetryofnucleationcentersactivityinultrathincofilmsandcoptmultilayers AT shapiroaj onthenatureofasymmetryofnucleationcentersactivityinultrathincofilmsandcoptmultilayers AT clchien onthenatureofasymmetryofnucleationcentersactivityinultrathincofilmsandcoptmultilayers AT shullrd onthenatureofasymmetryofnucleationcentersactivityinultrathincofilmsandcoptmultilayers |
first_indexed |
2025-07-10T03:29:07Z |
last_indexed |
2025-07-10T03:29:07Z |
_version_ |
1837229043640958976 |
fulltext |
2Q�WKH�QDWXUH�RI�DV\PPHWU\�RI�QXFOHDWLRQFHQWHUV�DFWLYLW\�LQ�XOWUDWKLQ�&R ILOPVDQG�&R�3W PXOWLOD\HUV
<X�/�,XQLQ��<X�3�.DEDQRY��9�,�1LNLWHQNR
�;�0�&KHQJ
��$�-�6KDSLUR
��&�/�&KLHQ
��5�'�6KXOO
,QVWLWXWH�RI�6ROLG�6WDWH�3K\VLFV��5XVVLDQ�$FDGHP\�RI�6FLHQFHV�
&KHUQRJRORYND����������5XVVLD
7KH�-RKQV�+RSNLQV�8QLYHUVLW\��%DOWLPRUH��0DU\ODQG��������86$
1DWLRQDO�,QVWLWXWH�RI�6WDQGDUGV�DQG�7HFKQRORJ\��*DLWKHUVEXUJ�
0DU\ODQG��������86$
5HFHLYHG�2FWREHU���������
0DJQHWL]DWLRQ�UHYHUVDO�LQ�XOWUDWKLQ�3W����QP��&R�����QP��3W���QP��PDJQHWLF�ILOPV�DQG
3W����QP��>&R�G��3W���QP�@Q�� 3W���QP�� �G� ������ ����� ���� QP��Q� ���� ���PXOWLOD\HUV� ZLWKSHUSHQGLFXODU�DQLVRWURS\�KDV�EHHQ�VWXGLHG�XVLQJ�.HUU�PLFURVFRS\��7KHVH�PDWHULDOV�GHPRQ�
VWUDWH� XQXVXDO� HIIHFWV� RI� DFWLYLW\� DV\PPHWU\� RI� QXFOHDWLRQ� FHQWHUV� DQG� GRPDLQ�ZDOO�PR�
WLRQ��7KH�ILHOG�GHSHQGHQFHV�RI�WKHVH�HIIHFWV�KDYH�EHHQ�VWXGLHG�DQG�WKH�DV\PPHWU\�RI�WKH
GRPDLQ�ZDOO�QXFOHDWLRQ�KDV�EHHQ�IRXQG�WR�EH�VXSSUHVVHG�E\�DSSOLFDWLRQ�RI�D�PDJQHWLF�ILHOG
PXFK� VWURQJHU� WKDQ� WKH� VDPSOH� FRHUFLYLW\�� 7KH� DV\PPHWU\� FRPHV� EDFN� DIWHU� VHYHUDO
UHYHUVDOV� DW� D� ORZHU� ILHOG� PDJQLWXGH�� 7KH� DV\PPHWU\� RI� GRPDLQ� ZDOO� YHORFLW\� GHFUHDVHV
DEUXSWO\�DQG�YDQLVKHV�DV�WKH�UHYHUVDO�ILHOG�LQFUHDVHV�LQ�ORZ�FRHUFLYLW\�XOWUDWKLQ�&R�ILOPV�
7KH�HIIHFW�UHFRYHUV�DV�LQ�WKH�UHYHUVDO�ILHOG�YDOXH�GHFUHDVHV��$�UROH�RI�WKH�&R�3W�LQWHUIDFH
GHIHFWV�DQG�QRQOLQHDU�VSLQ�H[FLWDWLRQV�LQ�WKHVH�SKHQRPHQD�LV�GLVFXVVHG�
lË�º�ºä� z˯¯�äÒ}¯º°}º¹ÒÒ� Ò°°ãË�ºmÈÓº� ¹Ë¯ËäÈ�ÓÒ�ÒmÈÓÒË� �ã �¯È�ºÓ}Ò²� äÈ�ÓÒ�Ó©²
¹ã£Óº}� 3W���� Óä��&R�����Óä��3W��Óä�� Ò� äÓº�º°ãº®Ó©²� °�¯�}��¯� 3W����Óä��
>&R�G��3W���Óä�@Q��3W���Óä�� �G� ���������������Óä��Q� ���� ��� °�¹Ë¯¹ËÓ�Ò}�㫯Ӻ®�ÈÓÒϺ��¯º¹ÒË®��¹¯º«mã«
�Ò²�ªÁÁË}�©�ȰÒääË�¯ÒÒ�È}�ÒmÓº°�Ò��ËÓ�¯ºm�ÏȯºÎ�ËÓÒ«�Ò��mÒÎË�
ÓÒ«��ºäËÓÓ©²� °�ËÓº}��j°°ãË�ºmÈÓÈ� ¹ºãËmÈ«� ÏÈmÒ°Ò亰� � ª�Ò²� ªÁÁË}�ºm��|Óȯ�ÎËÓº�
��º�¹¯ÒãºÎËÓÒË��º°�È�º�Óº�ºã �º�º�ÓȰ©�È
�Ë�º�¹ºã«��°��˰�mËÓÓº�¹¯Ëm©�È
�Ë�º
}ºª¯�Ò�ÒmÓº°� � º¯ÈÏ�È�� ¹º�Èmã«Ë�� È}�ÒmÓº°� � ȰÒääË�¯Ò�Ó©²� �ËÓ�¯ºm� ÏȯºÎ�ËÓÒ«�
�˯ËäÈ�ÓÒ�ÒmÈÓÒË� m� ¹ºã«²� äËÓ �Ë®� mËãÒ�ÒÓ©� ¹¯Òmº�Ò�� }� mº°°�ÈÓºmãËÓÒ
� ȰÒääË��
¯ÒÒ�� {� �ã �¯È�ºÓ}Ò²� ¹ã£Ó}Ȳ� &R� °� äÈ㺮� }ºª¯�Ò�ÒmÓº°�
� ȰÒääË�¯Ò«� °}º¯º°�Ë®
�ºäËÓÓ©²�°�ËÓº}�¯ËÏ}º��äËÓ �ÈË�°«�Ò�Ò°�ËÏÈË��°��mËãÒ�ËÓÒËä�¹ºã«��mº°°�ÈÓÈmãÒmÈ«°
°�Ë�º��äËÓ �ËÓÒËä��|°�Î�ÈË�°«�¯ºã �°�¯�}��¯©�äËÎÁÈÏÓº®��¯ÈÓÒ�©�&R�3W�Ò�ÓËãÒÓË®�
Ó©²�mºÏ�Î�ËÓÒ®�°¹ÒÓºmº®�¹º�°Ò°�Ëä©�m�Áº¯äÒ¯ºmÈÓÒÒ�ª�Ò²�ªÁÁË}�ºm�
7KH� DUWLILFLDO� XOWUDWKLQ� PDJQHWLF� ILOPV
DQG�PXOWLOD\HUV� FRPSRVHG� RI� IHUURPDJQHWLF
OD\HUV� VHSDUDWHG� E\� QRQPDJQHWLF� VSDFHUV
UHSUHVHQW� D� QHZ� W\SH� RI� TXDVL�WZR�GLPHQ�
VLRQDO�VWUXFWXUHV�ZLWK�SK\VLFDO�SURSHUWLHV�RI
D�JUHDW�LQWHUHVW��7KH�ORZHULQJ�RI�WKH�V\VWHP
GLPHQVLRQDOLW\� UHVXOWV� XVXDOO\� LQ� QHZ� DQG
TXDOLWDWLYHO\� GLIIHUHQW� SK\VLFDO� SURSHUWLHV�
,Q� SDUWLFXODU�� DV� WKH� WKLFNQHVV� RI�PDJQHWLF
OD\HUV� GHFUHDVHV� �EHFRPLQJ� OHVV� WKDQ� D� IHZ
DWRPLF� OD\HUV��� WKHVH� VWUXFWXUHV� FKDQJH
DEUXSWO\� WKH� HDV\� PDJQHWL]DWLRQ� D[LV� IURP
WKH�LQ�SODQH�WR�WKH�RXW�RI�SODQH��UHYHDOLQJ�D
VWURQJ� SHUSHQGLFXODU� PDJQHWLF� DQLVRWURS\
�30$��� ,QYHVWLJDWLRQV� RI� PDJQHWL]DWLRQ� UH�
YHUVDO�RI�XOWUDWKLQ� IHUURPDJQHWLF� ILOPV�DQG
)XQFWLRQDO�0DWHULDOV�����1R��������� ��������,QVWLWXWH�IRU�6LQJOH�&U\VWDOV
)XQFWLRQDO�PDWHULDOV������������� ��
PXOWLOD\HUV� ZLWK� 30$� KDYH� VKRZQ� WKDW
VRPH� UHPDJQHWL]DWLRQ� IHDWXUHV� DUH� VLPLODU
WR� WKRVH� RI� EXON� PDWHULDOV�� ,Q� SDUWLFXODU�
WKH�UHYHUVDO�LQ�XOWUDWKLQ�ILOPV�RFFXUV��DV�LQ
WKH� EXON� PDWHULDOV�� E\� WKH� QXFOHDWLRQ� DQG
VSUHDGLQJ� RI� GRPDLQ� ZDOOV� >��@�� 7KH� PR�
WLRQ�RI�GRPDLQ�ZDOOV�ZDV�IRXQG�WR�EH�HLWKHU
WKHUPDOO\� DFWLYDWHG� RU� YLVFRXV�� GHSHQGLQJ
XSRQ�WKH�PDJQHWLF�ILHOG�VWUHQJWK�>�@��
+RZHYHU�� RXU� UHFHQW� VWXG\� RI� XOWUDWKLQ
3W�>&R�3W@Q�3W�PXOWLOD\HUV� �Q� ����������KDVUHYHDOHG� VRPH� TXLWH� XQXVXDO� IHDWXUHV� LQ
WKHLU� PDJQHWL]DWLRQ� UHYHUVDO� EHKDYLRU� >�@
WKRVH� FDQ� QRW� EH� XQGHUVWRRG� LQ� WKH� IUDPH�
ZRUNV� RI� D� SHUIHFW� LQWHUIDFH� VWUXFWXUH�� ,Q
DGGLWLRQ� WR� WKH� XVXDO� V\PPHWULFDO� QXFOHD�
WLRQ� FHQWHUV�� KLWKHUWR� XQNQRZQ� DV\PPHWUL�
FDO� PDJQHWLF� GRPDLQ� QXFOHDWLRQ� FHQWHUV
ZHUH�IRXQG�LQ�XOWUDWKLQ�>&R�3W@Q�VWUXFWXUHVZLWK� Q� ���� ��� DQG� ��� ZKHUH� WKH� UHYHUVDO
EHJLQV� IRU� RQH� GLUHFWLRQ� RI� WKH� ILHOG� RQO\�
7KH�QHZ�GRPDLQV�QXFOHDWH�DW�GLIIHUHQW�SRVL�
WLRQV� IRU� PDJQHWL]DWLRQ�0� SRLQWLQJ� XS� RU
GRZQ��$�SURQRXQFHG�DV\PPHWU\� LQ� WKH�PR�
ELOLW\� RI� GRPDLQ� ZDOOV� LQ� VLQJOH� &R� ILOPV
ZLWK�ORZ�FRHUFLYLW\�ZDV�DOVR�UHSRUWHG��ZKLFK
LV�LQ�VKDUS�FRQWUDVW�WR�WKH�H[SHFWHG�V\PPH�
WU\� RI� PDJQHWLF� UHYHUVDO� LQ� JHQHUDO� LQ� WKH
KRPRJHQHRXV�EXON�IHUURPDJQHWV�
,Q� WKLV� ZRUN�� ZH� KDYH� VWXGLHG� LQ� GHWDLO
WKH� HOHPHQWDU\� UH�PDJQHWL]DWLRQ� HYHQWV� LQ
WKH� RXW�RI�SODQH� PDJQHWL]HG� XOWUDWKLQ
>&R�3W@Q��Q� ����������PXOWLOD\HUV�DV�D�IXQF�WLRQ� RI� WKH� VDWXUDWLRQ� ILHOG� DQG� QXPEHU� RI
OD\HUV�� :H� KDYH� VWXGLHG� WKH� PDQQHU� E\
ZKLFK� WKH� DV\PPHWULFDO� GRPDLQ� QXFOHDWLRQ
DFWLYLW\� GHSHQGV� RQ� WKH� VDWXUDWLRQ� ILHOG
PDJQLWXGH�� 7KH� GHSHQGHQFH� RI� WKH� GRPDLQ
ZDOO�YHORFLW\�DV\PPHWU\�RQ�WKH�DSSOLHG�ILHOG
ZDV�DOVR�LQYHVWLJDWHG�
7KH� VDPSOHV� WR� VWXG\� ZHUH� WKH
3W����QP��&R����� QP���3W��� QP�� ILOPV� DQG
3W����QP��>&R�G���3W���QP�@Q�3W���QP��PXO�WLOD\HUV� �Q� ���� ��� G� ������ ���� QP�� JURZQ
E\� '&� PDJQHWURQ� VSXWWHULQJ� RQWR� 6L�����
VXEVWUDWHV� DW� URRP� WHPSHUDWXUH�� 7KH� GR�
PDLQ� VWUXFWXUH� HYROXWLRQ� ZDV� LQYHVWLJDWHG
LQ� VLWX� E\� PDJQHWR�RSWLFDO� .HUU� HIIHFW
�02.(�� PLFURVFRS\� DW� YDULRXV� PDJQHWLF
ILHOGV�� DSSOLHG� SHUSHQGLFXODU� WR� WKH� ILOP
SODQH��7KH�DYHUDJH�PDJQHWL]DWLRQ�DV�D�IXQF�
WLRQ� RI� WKH� DSSOLHG� PDJQHWLF� ILHOG� +� ZDV
GHWHUPLQHG� E\� +DOO� UHVLVWDQFH� PHDVXUH�
PHQWV�DW�+�SHUSHQGLFXODU�WR�WKH�ILOP�SODQH�
6LQFH� WKH� H[WUDRUGLQDU\�+DOO� UHVLVWDQFH�5+LQ�PXOWLOD\HUV�ZLWK�30$�LV�SURSRUWLRQDO�WR
0��WKH�ILHOG�GHSHQGHQFH�RI�5+�\LHOGV�WKH�FXUYH0�+���7KH�>&R�3W@Q�VDPSOHV�ZLWK�Q� �������DQG��VKRZ�VTXDUH�K\VWHUHVLV�ORRSV��H�J���VHH�)LJ�����
WKHLU�FRHUFLYLW\�+F� LQFUHDVHV�ZLWK�WKH�QXP�EHU� RI� &R� OD\HUV�� 7R� VWXG\� WKH� QXFOHDWLRQ
DQG� HYROXWLRQ� RI� GRPDLQV�� WKH� ILHOG� ZDV
JUDGXDOO\�UHGXFHG�IURP�WKH�VDWXUDWLRQ�ILHOG
+V�WR�D�UHYHUVHG�ILHOG�H[FHHGLQJ�WKH�VDPSOHFRHUFLYLW\�WLOO� WKH�GRPDLQ�QXFOHDWLRQ�RFFXUV
DQG�WKHQ�ZDV�NHSW�FRQVWDQW�
,Q� WKH� HDUOLHU� ZRUN� >�@�� ZH� KDYH� VKRZQ
DQ� H[DPSOH� RI� WKH� GRPDLQ� VWUXFWXUH� HYROX�
WLRQ�LQ�WKH�>&R�3W@��VWUXFWXUH��,Q�WKLV�ZRUN�ZH� LOOXVWUDWH� WKH� HYROXWLRQ� RI� GRPDLQV� LQ
WKH� XOWUDWKLQ� &R����� QP�� ILOP� �)LJ������ $
PDJQHWLF� ILHOG� RI� P�+� �����P7� �)LJ���D��E���F��DQG�P�+� ������P7��)LJ���G���H���I�ZDV�DSSOLHG�DIWHU�WKH�JUDGXDO�GHFUHDVH�IURP
WKH�VDWXUDWLQJ�ILHOGV�RI�P�+V� �����P7�DQG���P7��UHVSHFWLYHO\��7KH�PDJQHWL]DWLRQ�UH�
YHUVDO�LQ�VLQJOH�&R�XOWUDWKLQ�ILOPV�LV�VHHQ�WR
RFFXU�WKURXJK�WKH�QXFOHDWLRQ�DQG�JURZWK�RI
EXEEOH�GRPDLQV�OLNH�LQ�>&R�3W@��PXOWLOD\HUV�6LPLODU� WR� WKH� EXON� PDWHULDOV� DQG� WKLQ
ILOPV�� WKHUH� DUH� �V\PPHWULF�� GRPDLQ� ZDOOV
QXFOHDWLQJ� DW� WKH� VDPH� SRVLWLRQV� LQ� WKH
ILHOGV�ZLWK�RSSRVLWH�GLUHFWLRQV��+RZHYHU��DV
ZHOO� DV� LQ� >&R�3W@��� ZH� REVHUYHG� QRW� RQO\XVXDO� V\PPHWULFDO�� EXW� DOVR� WKH� XQXVXDO
DV\PPHWULFDO� QXFOHDWLRQ� FHQWHUV� LQ� VLQJOH
&R�OD\HUV��6XFK��DV\PPHWULFDO��W\SHV�RI�QX�
FOHDWLRQ�FHQWHUV�SURGXFH�GRPDLQV�RI�D�VLQJOH
PDJQHWL]DWLRQ� GLUHFWLRQ� RQO\�� HLWKHU� GRZQ�
ZDUG�RU�XSZDUG��EXW�QRW�ERWK��7KH�GRPDLQ
QXFOHDWHG�DW�WKH�ILHOG�GLUHFWHG�XSZDUG�RQO\
LV�VKRZQ�LQ�)LJV���H�DQG��I�E\�DUURZV�
7KH� GLIIHUHQFH� PDQLIHVWV� LWVHOI� DOVR� LQ
WKH� IDFW� WKDW� WKH� PDJQHWLF� ILHOG� UHYHUVLQJ
EHIRUH� WKH� �V\PPHWULFDO�� GRPDLQ� ZDOO
UHDFKHG�WKH�VDPSOH�ERXQGDULHV��RU�RWKHU�GR�
PDLQV�� UHVXOWV�QRW� RQO\� LQ� WKH� VKULQNLQJ�RI
D� GRPDLQ�� EXW� DOVR� LQ� WKH� IRUPDWLRQ� RI� D
ULQJ� VWUXFWXUH� GXH� WR� QXFOHDWLRQ� RI� D� QHZ
GRPDLQ�DW�WKH�VDPH�QXFOHDWLRQ�FHQWHU�>����@�
)LJ����� +\VWHUHVLV� ORRS� IRU� WKH� XOWUDWKLQ� &R
�����QP��ILOP�
<X�/�,XQLQ�HW�DO����2Q�WKH�QDWXUH�RI�DV\PPHWU\����
�� )XQFWLRQDO�PDWHULDOV�������������
+RZHYHU�� GXH� WR� WKH� DV\PPHWU\� LQ� QXFOHD�
WLRQ�DFWLYLW\��WKH�VKULQNLQJ�RI�DQ��DV\PPHW�
ULFDO��GRPDLQ�LV�REVHUYHG�RQO\��ZLWKRXW�IRU�
PDWLRQ�RI�D�ULQJ�VWUXFWXUH�
:H� KDYH� VWXGLHG� LQ� GHWDLO� WKH� H[LVWHQFH
FRQGLWLRQV� RI� WKLV� HIIHFW�� 2XU� H[SHULPHQWV
KDYH� UHYHDOHG� WKDW� WKH� DV\PPHWULF� QXFOHD�
WLRQ� LQ� WKH� VLQJOH� OD\HU� &R� ILOPV� DQG
>&R�3W@Q� PXOWLOD\HUV� �Q� ���� ��� LV� REVHUYHGDW�ORZ�VDWXUDWLQJ�ILHOGV��,W�LV�VXSSUHVVHG�E\
WKH�UDPSLQJ�XS�WR�KLJK�VDWXUDWLQJ�ILHOG��E\
DQ�RUGHU�RU�WZR�KLJKHU�WKDQ�WKH�PDFURVFRSLF
VDPSOH�FRHUFLYLW\��PHDVXUHG�E\�WKH�K\VWHUH�
VLV�ORRS���7KH�DV\PPHWU\�VXSSUHVVLRQ�LQ�WKH
GRPDLQ� QXFOHDWLRQ� E\� DSSOLFDWLRQ� RI� D� KLJK
ILHOG�KDV�EHHQ�UHYHDOHG�LQ�DOO�RI�WKH�>&R�3W@Q�Q� ���� ��� ��� VDPSOHV� VWXGLHG� LQ� WKLV�ZRUN�
7KH� ILHOG� YDOXH� DW� ZKLFK� WKH� QXFOHDWLRQ
DV\PPHWU\� LV� VXSSUHVVHG�YDULHV� IRU�YDULRXV
VDPSOHV��:H�KDYH�IRXQG�DOVR�WKDW�WKH�DV\P�
PHWULF� QXFOHDWLRQ� UHDSSHDUHG� DIWHU� VHYHUDO
UHYHUVDO� F\FOHV� SURFHHGLQJ� IURP� D� ILHOG
ORZHU�WKDW�WKH�VDWXUDWLQJ�RQH��
)LJ����� 02.(� LPDJHV� RI� WKH� HYROXWLRQ� RI� D� GRPDLQ� VWUXFWXUH� LQ� WKH� XOWUDWKLQ�&R� ����� QP�� ILOP
XQGHU�DSSOLFDWLRQ�RI�PDJQHWLF�ILHOGV�P�+� �����P7��D��E��F��DQG�P�+� ������P7��G��H��I���UHVSHF�WLYHO\��DUURZV�VKRZ�WKH�GRPDLQV�SURGXFHG�E\��DV\PPHWULF��FHQWHUV��
<X�/�,XQLQ�HW�DO����2Q�WKH�QDWXUH�RI�DV\PPHWU\����
)XQFWLRQDO�PDWHULDOV������������� ��
7KLV� SKHQRPHQRQ�PD\� EH� GXH� WR� VHYHUDO
UHDVRQV��)LUVW�� LW� FDQ�EH�GHILQHG�E\� WKH�GH�
IHFW� VWUXFWXUH� SHFXOLDULWLHV� RI� UHDO� WKLQ
ILOPV�� ,W� LV� NQRZQ� WKDW� WKH� DGVRUSWLRQ� RI
DWRPV� RQ� WKH� ILOP� VXUIDFH� IURP� WKH� JDV
SKDVH� DOZD\V� RFFXUV� ZLWK� IRUPDWLRQ� DQG
JURZWK�RI�LVODQGV��6R��VXFK�HOHPHQWV�RI�WKH
LQWHUIDFH� VWUXFWXUH� DV� LVODQGV�� VWHSV�� DQG
SLQKROHV� DUH� LQHYLWDEOH� SDUW� RI� QDQRFRPSR�
VLWHV��7KHLU�UROH� LQ�WKH�SURFHVVHV�RI�QXFOHD�
WLRQ� DQG� GRPDLQ�ZDOO�PRWLRQ� LQ� TXDVL� WZR�
GLPHQVLRQDO�VWUXFWXUHV�LV�VWLOO�SRRUO\�XQGHU�
VWRRG��
7KH� DV\PPHWULFDO� QXFOHDWLRQ� FHQWHUV
KDYH� EHHQ� REVHUYHG� EHIRUH�� EXW� RQO\� LQ� WKH
H[FKDQJH� FRXSOHG� WKLQ� IHUURPDJQHWLF�DQWLI�
HUURPDJQHWLF� ELOD\HUV� >����@�� 6LPLODUO\�� LQ
RXU�VDPSOHV�� WKH�DV\PPHWU\�PD\�EH�FDXVHG
E\� WKH� IRUPDWLRQ� RI� D� ORFDO� XQLGLUHFWLRQDO
DQLVRWURS\� GXH� WR� H[FKDQJH� FRXSOLQJ� EH�
WZHHQ�LVODQGV�ZLWK�IHUURPDJQHWLF�DQG�DQWLI�
HUURPDJQHWLF� RUGHULQJ�� 7KH� DQWLIHUURPDJ�
QHWLF�RUGHULQJ�PD\�RFFXU�HLWKHU�GXH�WR�R[L�
GDWLRQ� RI� VRPH�&R� LVODQGV� DQG�&R2� IRUPD�
WLRQ� RI� >�@� �LI� VXSSRVH� WKDW� WKH� 1HHO� WHP�
SHUDWXUH� IRU� WKH�&R2�QDQRLVODQGV� LV�KLJKHU
WKDQ� WKDW� IRU� WKH� EXON� R[LGH��� RU� DW� WKH
LQWHUIDFLDO�VWHSV�>�@��RU�DW�WKH�&R�VXUIDFH�DV
SUHYLRXVO\� REVHUYHG� LQ� DQ� )H�:������ XO�
WUDWKLQ� ILOP� >�@�� 0RUHRYHU�� WKH� DV\PPHWU\
PD\�EH�GXH�WR�GHIHFWV�LQ�WKH�LQWHUIDFH�VWUXF�
WXUH�VXFK�DV�LVODQGV�ZLWK�YHU\�KLJK�FRHUFLY�
LW\� DQG� RSSRVLWH� PDJQHWL]DWLRQ� GLUHFWLRQ
>��@��$QRWKHU�UHDVRQ�IRU�WKH�DV\PPHWULF�QX�
FOHDWLRQ�PD\� EH� UHODWHG� WR� WKH� H[LVWHQFH� RI
DQ� XQXVXDO� VSLQ� FRQILJXUDWLRQ� NQRZQ� DV� D
VN\UPLRQ�>������@��,I�VN\UPLRQV�UHPDLQ�VWD�
EOH�DJDLQVW�FROODSVH�WR�WKH�DWRPLF�VFDOH��WKH
GRZQ� GRPDLQV� VKULQN� WR� D� VPDOO� EXW� ILQLWH
UDGLXV� LQ� DQ� XSZDUG� ILHOG� DQG� UHDSSHDU
ZKHQ�WKH�ILHOG�LV�UHYHUVHG��
:H�KDYH�DOVR�VWXGLHG�WKH�DV\PPHWU\�H[�
LVWHQFH�FRQGLWLRQV�LQ�WKH�YHORFLW\�RI�WKH�GR�
PDLQ� ZDOOV�� 7R� PHDVXUH� WKH� GRPDLQ� ZDOO
YHORFLWLHV�� WKH�PDJQHWLF�ILHOG�ZDV�NHSW�FRQ�
VWDQW� DIWHU� QXFOHDWLRQ� RI� GRPDLQV� DQG� WKH
GRPDLQ� ZDOO� GLVSODFHPHQW�ZDV�PHDVXUHG� DV
D� IXQFWLRQ� RI� WLPH�� 7KH� GLVSODFHPHQWV� DUH
OLQHDU� LQ� WLPH��ZLWK� D�ZHOO�GHILQHG�YHORFLW\
�)LJ������8QOLNH�WKH��V\PPHWULFDO��GRPDLQV�
WKH� GRPDLQ� ZDOOV� QXFOHDWHG� DW� �DV\PPHWUL�
FDO�� FHQWHUV� LQ� VLQJOH�&R� ILOPV� KDYH� EDFN�
ZDUG� YHORFLWLHV� VLJQLILFDQWO\� ODUJHU� WKDQ
WKDW�RI�GRPDLQ�ZDOO�JURZWK�LQ�D�ILHOG�RI�WKH
VDPH� VWUHQJWK� EXW� RSSRVLWH� GLUHFWLRQ�� )LJ�
XUH� �� VKRZV� WKH� IRUZDUG� DQG� EDFNZDUG
�DV\PPHWULFDO�� GRPDLQ� ZDOO� GLVSODFHPHQWV
LQ�WKH�VLQJOH�XOWUDWKLQ�&R�ILOP��PHDVXUHG�DW
WZR� GLIIHUHQW� DSSOLHG�PDJQHWLF� ILHOGV�� DV� D
IXQFWLRQ� RI� WLPH�� 2QH� FDQ� VHH� WKDW� WKH
)LJ�����)RUZDUG��RSHQ�V\PEROV��DQG�EDFNZDUG
�ILOOHG� V\PEROV�� GLVSODFHPHQWV� RI� WKH� �DV\P�
PHWULF�� GRPDLQ� ZDOO� LQ� WKH� XOWUDWKLQ� VLQJOH
&R����� QP�� ILOP� ZLWK� WKH� FRHUFLYLW\� P�+F� ����P7� DV� D� IXQFWLRQ� RI� WLPH� XQGHU� DSSOLHG
PDJQHWLF� ILHOGV� �D�� P�+� �r����� P7� DQG� �E�
r�����P7��6ROLG�OLQHV�DUH�WKH�OLQHDU�ILWV��
)LJ����� 5DWLR� RI� WKH� IRUZDUG� DQG� EDFNZDUG
YHORFLWLHV� RI� �DV\PPHWULF�� GRPDLQ� ZDOOV� LQ
WKH�&R�����QP��ILOP�DV�D�IXQFWLRQ�RI�DSSOLHG
PDJQHWLF�ILHOG��6ROLG�OLQH�JXLGHV�IRU�H\HV��
<X�/�,XQLQ�HW�DO����2Q�WKH�QDWXUH�RI�DV\PPHWU\����
�� )XQFWLRQDO�PDWHULDOV�������������
ODUJHU�WKH�PDJQHWLF�ILHOG��WKH�OHVV�WKH�UDWLR
RI�EDFNZDUG�DQG�IRUZDUG�YHORFLWLHV��
)LJXUH� �� VKRZV� WKH� ILHOG� GHSHQGHQFH� RI
WKH� GRPDLQ� ZDOO� YHORFLW\� DV\PPHWU\� �UDWLR
RI� WKH� EDFNZDUG� WR� WKH� IRUZDUG� YHORFLW\�
REWDLQHG� ZLWK� RQH� PRUH� XOWUDWKLQ�&R� ILOP�
2QH� FDQ� VHH� WKDW� WKH� DV\PPHWU\� RI�GRPDLQ
ZDOO�PRELOLW\� YDQLVKHV� FRPSOHWHO\� DW� ODUJHU
PDJQHWLF� ILHOGV�� 7KLV� HIIHFW� LV� REVHUYHG� LQ
WKH�VLQJOH�&R�ILOPV�ZLWK�ORZ�FRHUFLYLW\�RQO\
�P�+Fa��P7���LW�GRHV�QRW�DSSHDU�ERWK�LQ�WKHVLQJOH�OD\HU�&R�ILOP�ZLWK�D�ODUJHU�FRHUFLYLW\
�P�+F� �����P7��DQG�LQ�WKH�>&R�3W@��VDPSOH�P�+F� ����P7���ZKHUH�GRPDLQ�ZDOOV�GR�QRWPRYH� LQ� ILHOGV� P�+d��P7��7KLV� DV\PPHWUL�
FDO� SKHQRPHQRQ� KDV� QHYHU� EHHQ� SUHGLFWHG�
DQG� LWV� RULJLQ� UHPDLQV� XQFOHDU�� 'RPDLQ
ZDOOV� QXFOHDWHG� DW� �V\PPHWULFDO�� DQG
�DV\PPHWULFDO�� FHQWHUV� RYHUFRPH� VLPLODU
EDUULHUV� GXULQJ� WKHLU� PRWLRQ� EXW� GLVSOD\
GLIIHUHQW�EDFNZDUG�YHORFLWLHV��&RQVHTXHQWO\�
RQH�PD\� VXVSHFW� GLIIHUHQW� W\SHV� RI� FHQWHUV
IRUP�GLIIHUHQW�GRPDLQ�ZDOO�VWUXFWXUHV���
,Q� FRQFOXVLRQ�� ZH� KDYH� VWXGLHG� LQ� GHWDLO
IHDWXUHV� RI� WKH� PDJQHWL]DWLRQ� UHYHUVDO� RI
VSXWWHUHG� XOWUDWKLQ� &R� ILOPV� DQG� >&R�3W@Q�Q� ���� ��� PXOWLOD\HUV� ZLWK� SHUSHQGLFXODU
PDJQHWLF� DQLVRWURS\�� 7KH� DV\PPHWULFDO� DF�
WLYLW\� RI� WKH� GRPDLQ� QXFOHDWLRQ� FHQWHUV� LV
VXSSUHVVHG� UHYHUVLEO\� E\� WKH� DSSOLFDWLRQ� RI
ODUJH� PDJQHWLF� ILHOGV� LQ� DOO� RI� WKH� VDPSOHV�
7KH�DV\PPHWU\�RI�GRPDLQ�ZDOO�YHORFLW\��EHLQJ
UHYHDOHG� RQO\� LQ� WKH� XOWUDWKLQ�&R�ILOPV�ZLWK
ORZ�FRHUFLYLW\��GHFUHDVHV�DQG�GLVDSSHDUV�FRP�
SOHWHO\�DW�ODUJHU�PDJQHWLF�ILHOGV�
7KLV�ZRUN�ZDV�VXSSRUWHG�LQ�SDUW�E\�%DVLF
5HVHDUFK� 3URJUDP� RI� WKH� 5$6� 3UHVLGLXP
3�����4XDQWXP�0DFURSK\VLFV��
5HIHUHQFHV
� ���-�3RPPLHU��3�0H\HU��*�3HQLVVDUG�HW�DO���3K\V�
5HY��/HWW�������������������
� ���$�.LULO\XN��-�)HUUH��9�*UROLHU�HW�DO���-��0DJQ�
0DJQ��0DWHU������������������
� ���0�.LVLHOHZVNL�� $�0D]LHZVNL�� 0�7HNLHODN� HW
DO���-��0DJQ��0DJQ��0DWHU�������������������
� ���<�/�,XQLQ��<�3�.DEDQRY��9�,�1LNLWHQNR�HW�DO��
3K\V��5HY��/HWW���������������������
� ���9�,�1LNLWHQNR�� 9�6�*RUQDNRY�� /�0�'HGXNK� HW
DO���3K\V��5HY��%������5������������
� ���9�,�1LNLWHQNR�� 9�6�*RUQDNRY�� $�-�6KDSLUR� HW
DO���3K\V��5HY��/HWW������������������
� ���:�+�0HLNOHMRKQ�� &�3�%HDQ�� 3K\V��5HY��� ����
������������
� ���5�6NRPVNL�� +�3�2HSHQ�� -�.LUVFKQHU�� 3K\V�
5HY��%�������������������
� ���$�.XEHW]ND��3�)HUULDQL��0�%RGH� HW� DO���3K\V�
5HY��/HWW���������������������
����2�3LHW]VFK��$�.XEHW]ND��0�%RGH� HW� DO���3K\V�
5HY��/HWW���������������������
����$�$EDQRY�� 9�/�3RNURYVN\�� 3K\V��5HY��%�� ���
5������������
����$�6�.LUDNRV\DQ�� 9�/�3RNURYVN\�� -��0DJQ�
0DJQ��0DWHU�������������������
�¯º�¹¯Ò¯º���ȰÒäË�¯L��È}�ÒmÓº°�L��ËÓ�¯LmÏȯº�ÎËÓÓ«�m��ã �¯È�ºÓ}Ò²�¹ãLm}Ȳ�&R�È�È�È�º�ȯºmÒ²�°�¯�}��¯È²�&R�3W
����,�ÓLÓ������zÈÈÓºm��{�,�sL}L�ËÓ}º�¡�l� ËÓ ��k�iÎ�bȹL¯º��v��� L¼Ó��c�i�bÈãã
lË�º�ºä� z˯¯�äL}¯º°}º¹L�� �º°ãL�ÎËÓº� ¹Ë¯ËäÈ�ÓL��mÈÓÓ«� �ã �¯È�ºÓ}Ò²� äÈ�ÓL�ÓÒ²
¹ãLmº}�3W����Óä��&R�����Óä���3W���Óä�� �È� È�È�º�ȯºmÒ²�°�¯�}��¯�3W����Óä���>&R�G��3W
���Óä�@Q�3W���Óä���G� ���������������Óä��Q� �������Ï�¹Ë¯¹ËÓ�Ò}�㫯Ӻ
�ÈÓLϺ�¯º¹L¼
��«}LmÒ«mã«
� �ËÁË}�Ò�ȰÒäË�¯L��È}�ÒmÓº°�L��ËÓ�¯Lm�Ïȯº�ÎËÓÓ«��È�¯�²���ºäËÓÓÒ²�°�LÓº}�
iº°ãL�ÎËÓº�¹ºã ºm��ÏÈãËÎÓL°� ��Ò²�ËÁË}�Lm��~�«°ºmÈÓº���º�¹¯Ò}ãÈ�ÈÓÓ«��º°Ò� �°Òã �
Óº�º� ÓȰÒ��mÈã Óº�º� ¹ºã«� �«}Ë� L°�º�Óº� ¹Ë¯ËmÒ��¼� }ºË¯�Ò�ÒmÓL°� � ϯÈÏ}È�� ¹¯Ò�ÓL��¼
È}�ÒmÓL°� �ȰÒäË�¯Ò�ÓÒ²��ËÓ�¯Lm�Ïȯº�ÎËÓÓ«���˯ËäÈ�ÓL��mÈÓÓ«�m�¹ºã«²�äËÓ�º��mËãÒ�Ò�
ÓÒ�¹¯Òmº�Ò� ��º�mL�ÓºmãËÓÓ«�ȰÒäË�¯L���{��ã �¯È�ºÓ}Ò²�¹ãLm}Ȳ�&R�Ï�äÈãº
�}ºË¯�Ò�ÒmÓL°�
�
� ȰÒäË�¯L«��mÒ�}º°�Ë®��ºäËÓÓÒ²� °�LÓº}�¯LÏ}º� ÏäËÓ��¼� °«� �È� ÏÓÒ}ȼ�¹¯Ò� ÏLã �ËÓÓL
¹ºã«��mL�Óºmã
�Ò° �¹¯Ò�®º�º�ÏäËÓ�ËÓÓL��|�ºmº¯
¼� °«�¯ºã �°�¯�}��¯Ò�äLÎÁÈÏÓº��äËÎL
&R�3W��È�ÓËãLÓL®ÓÒ²�Ï��ÎËÓ �°¹LÓºmº��¹L�°Ò°�ËäÒ���Áº¯ä�mÈÓÓL��Ò²�ËÁË}�Lm�
<X�/�,XQLQ�HW�DO����2Q�WKH�QDWXUH�RI�DV\PPHWU\����
)XQFWLRQDO�PDWHULDOV������������� ��
|