We have observed charge-ordering-induced polar domains and domain walls (DWs) in a bilayered manganite Pr(Sr0.15Ca0.85)2Mn2O7 using second-harmonic-generation microscopy. Around the transition temperature TC306K, a nucleation process of the domains with spontaneous polarization is clearly observed. Well below TC, the characteristic band-shaped dark patterns are identified in the second-harmonic images. On the analogy of the nucleation feature, they can be assigned to the DWs separating antiparallel polar domains. The anisotropy in the DW is governed by the geometrical constraint of the charge and orbital ordering, not by the electrostatic stability as in conventional ferroelectric DWs.

2.
Y. -H.
Shin
,
I.
Grinberg
,
I. -W.
Chen
, and
A. M.
Rappe
,
Nature (London)
449
,
881
(
2007
).
3.
C. -L.
Jia
,
S. -B.
Mi
,
K.
Urban
,
I.
Vrejoiu
,
M.
Alexe
, and
D.
Hesse
,
Nature Mater.
7
,
57
(
2008
).
4.
S. -W.
Cheong
and
M.
Mostovoy
,
Nature Mater.
6
,
13
(
2007
).
5.
G.
Catalan
,
H.
Béa
,
S.
Fusil
,
M.
Bibes
,
P.
Paruch
,
A.
Barthélémy
, and
J. F.
Scott
,
Phys. Rev. Lett.
100
,
027602
(
2008
).
6.
F.
Kagawa
,
M.
Mochizuki
,
Y.
Onose
,
H.
Murakawa
,
Y.
Kaneko
,
N.
Furukawa
, and
Y.
Tokura
,
Phys. Rev. Lett.
102
,
057604
(
2009
).
7.
J.
Seidel
,
L. W.
Martin
,
Q.
He
,
Q.
Zhan
,
Y. -H.
Chu
,
A.
Rother
,
M. E.
Hawkridge
,
P.
Maksymovych
,
P.
Yu
,
M.
Gajek
,
N.
Balke
,
S. V.
Kalinin
,
S.
Gemming
,
F.
Wang
,
G.
Catalan
,
J. F.
Scott
,
N. A.
Spaldin
,
J.
Orenstein
, and
R.
Ramesh
,
Nature Mater.
8
,
229
(
2009
).
8.
D. V.
Efremov
,
J. d.
Brink
, and
D. I.
Khomskii
,
Nature Mater.
3
,
853
(
2004
).
9.
J.
van den Brink
and
D. I.
Khomskii
,
J. Phys.: Condens. Matter
20
,
434217
(
2008
).
10.
N.
Ikeda
,
H.
Ohsumi
,
K.
Ohwada
,
K.
Ishii
,
T.
Inami
,
K.
Kakurai
,
Y.
Murakami
,
K.
Yoshii
,
S.
Mori
,
Y.
Horibe
, and
H.
Kitô
,
Nature
436
,
1136
(
2005
).
11.
Y.
Tokunaga
,
Th.
Lottermoser
,
Y.
Lee
,
R.
Kumai
,
M.
Uchida
,
T.
Arima
, and
Y.
Tokura
,
Nature Mater.
5
,
937
(
2006
).
12.
Y.
Tokura
and
N.
Nagaosa
,
Science
288
,
462
(
2000
).
13.
Y.
Tokura
,
Rep. Prog. Phys.
69
,
797
(
2006
).
14.
Y.
Tokunaga
,
T. J.
Sato
,
M.
Uchida
,
R.
Kumai
,
Y.
Matsui
,
T.
Arima
, and
Y.
Tokura
,
Phys. Rev. B
77
,
064428
(
2008
).
15.
Y. S.
Lee
,
Y.
Tokunaga
,
T.
Arima
, and
Y.
Tokura
,
Phys. Rev. B
75
,
174406
(
2007
).
16.
Y. S.
Lee
,
Y.
Tokunaga
,
T.
Lottermoser
,
Y. K.
Seo
,
T.
Arima
, and
Y.
Tokura
,
J. Korean Phys. Soc.
51
,
1753
(
2007
).
17.
M.
Fiebig
,
V. V.
Pavlov
, and
R. V.
Pisarev
,
J. Opt. Soc. Am. B
22
,
96
(
2005
).
18.
Y.
Uesu
,
S.
Kurimura
, and
Y.
Yamamoto
,
Appl. Phys. Lett.
66
,
2165
(
1995
).
19.
D.
Meier
,
M.
Maringer
,
Th.
Lottermoser
,
P.
Becker
,
L.
Bohatý
, and
M.
Fiebig
,
Phys. Rev. Lett.
102
,
107202
(
2009
).
20.
Y. R.
Shen
,
The Principles of Nonlinear Optics
(
Wiley
,
New York
,
1984
).
21.
M.
Fiebig
,
D.
Fröhlich
,
T.
Lottermoser
, and
M.
Maat
,
Phys. Rev. B
66
,
144102
(
2002
).
22.
C.
Cen
,
S.
Thiel
,
G.
Hammerl
,
C. W.
Schneider
,
K. E.
Andersen
,
C. S.
Hellberg
,
J.
Mannhart
, and
J.
Levy
,
Nature Mater.
7
,
298
(
2008
).
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