Ferroelectric domain wall conductivity (DWC) is an intriguing and promising functional property that can be elegantly controlled and steered through a variety of external stimuli such as electric and mechanical fields. Optical-field control, as a noninvasive and flexible tool, has rarely been applied so far, but it significantly expands the possibility for both tuning and probing DWC. On the one hand, as known from second-harmonic or Raman micro-spectroscopy, the optical approach provides information on DW distribution and inclination, while simultaneously probing the DW vibrational modes; on the other hand, photons might be applied to directly generate charge carriers, thereby acting as a functional and spectrally tunable probe to deduce the local absorption properties and bandgaps of conductive DWs. Here, we report on investigating the photo-induced DWC (PI-DWC) of three lithium niobate crystals, containing a very different number of DWs, namely: (A) none, (B) one, and (C) many conductive DWs. All three samples are inspected for their current–voltage behavior in darkness and for different illumination wavelengths swept from 500 nm down to 310 nm. All samples show their maximum PI-DWC at 310 nm; moreover, sample (C) reaches PI-DWCs of several microampere. Interestingly, a noticeable PI-DWC is also observed for sub-bandgap illumination, hinting toward the existence and decisive role of electronic in-gap states that contribute to the electronic charge transport along DWs. Finally, complementary conductive atomic force microscopy investigations under illumination proved that the PI-DWC indeed is confined to the DW area and does not originate from photo-induced bulk conductivity.
REFERENCES
1.
M.
Fiebig
,
T.
Lottermoser
,
D.
Meier
, and
M.
Trassin
, “
The evolution of multiferroics
,” Nat. Rev. Mater.
1
, 16046
(2016
).2.
D.
Meier
and
S. M.
Selbach
, “
Ferroelectric domain walls for nanotechnology
,” Nat. Rev. Mater.
7
, 157
(2021
).3.
Y.
Zheng
and
W. J.
Chen
, “
Characteristics and controllability of vortices in ferromagnetics, ferroelectrics, and multiferroics
,” Rep. Prog. Phys.
80
, 086501
(2017
).4.
G.
Catalan
,
J.
Seidel
,
R.
Ramesh
, and
J. F.
Scott
, “
Domain wall nanoelectronics
,” Rev. Mod. Phys.
84
, 119
(2012
).5.
P.
Sharma
,
Q.
Zhang
,
D.
Samdo
,
C. H.
Lei
,
Y. Y.
Liu
,
J. Y.
Li
,
V.
Nagarajan
, and
J.
Seidel
, “
Nonvolatile ferroelectric domain wall memory
,” Sci. Adv.
3
, e1700512
(2017
).6.
J.
Seidel
and
L. M.
Eng
, “
Shedding light on nanoscale ferroelectrics
,” Curr. Appl. Phys.
14
, 1083
(2014
).7.
S.
Trolier-McKinstry
, “
Impact of ferroelectricity
,” Am. Ceram. Soc. Bull.
99
, 22
–23
(2020
).8.
K.
Yao
,
S. T.
Chen
,
S. C.
Lai
, and
Y. M.
Yousry
, “
Enabling distributed intelligence with ferroelectric multifunctionalities
,” Adv. Sci.
9
, 2103842
(2022
).9.
S.
Boyn
,
J.
Grollier
,
G.
Lecerf
,
B.
Xu
,
N.
Locatelli
,
S.
Fusil
,
S.
Girod
,
C.
Carrétéro
,
K.
Garcia
,
S.
Xavier
,
J.
Tomas
,
L.
Bellaiche
,
M.
Bibes
,
A.
Barthélémy
,
S.
Saïghi
, and
V.
Garcia
, “
Learning through ferroelectric domain dynamics in solid-state synapses
,” Nat. Commun.
8
, 14736
(2017
).10.
M. K.
Kim
and
J.-S.
Lee
, “
Ferroelectric analog synaptic transistors
,” Nano Lett.
19
(3
), 2044
–2050
(2019
).11.
P.
Sharma
,
T. S.
Moise
,
L.
Colombo
, and
J.
Seidel
, “
Roadmap for ferroelectric domain wall nanoelectronics
,” Adv. Funct. Mater.
32
, 2110263
(2022
).12.
H. Y.
Sun
,
J. R.
Wang
,
Y. S.
Wang
,
C. Q.
Guo
,
J. H.
Gu
,
W.
Mao
,
J. F.
Yang
,
Y. W.
Liu
,
T. T.
Zhang
,
T. Y.
Gao
,
H. Y.
Fu
,
T. J.
Zhang
,
Y. F.
Hao
,
Z. B.
Gu
,
P.
Wang
,
H. B.
Huang
, and
Y. F.
Nie
, “
Nonvolatile ferroelectric domain wall memory integrated on silicon
,” Nat. Commun.
13
, 4332
(2022
).13.
J.
Wang
,
J.
Ma
,
H. B.
Huang
,
J.
Ma
,
H. M.
Jafri
,
Y. Y.
Fan
,
H. Y.
Yang
,
Y.
Wang
,
M. F.
Chen
,
D.
Liu
,
J. X.
Zhang
,
Y.-H.
Lin
,
L.-Q.
Chen
,
D.
Yi
, and
C.-W.
Nan
, “
Ferroelectric domain-wall logic units
,” Nat. Commun.
13
, 3255
(2022
).14.
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
, “
Conduction at domain walls in oxide multiferroics
,” Nat. Mater.
8
, 229
(2009
).15.
N.
Balke
,
B.
Winchester
,
W.
Ren
,
Y. H.
Chu
,
A. N.
Morozovska
,
E. A.
Eliseev
,
M.
Huijben
,
R. K.
Vasudevan
,
P.
Maksymovych
,
J.
Britson
,
S.
Jesse
,
I.
Kornev
,
R.
Ramesh
,
L.
Bellaiche
,
L. Q.
Chen
, and
S. V.
Kalinin
, “
Enhanced electric conductivity at ferroelectric vortex cores in BiFeO3
,” Nat. Phys.
8
, 81
(2012
).16.
A.
Tselev
,
P.
Yu
,
Y.
Cao
,
L. R.
Dedon
,
L. W.
Martin
,
S. V.
Kalinin
, and
P.
Maksymovych
, “
Microwave a.c. conductivity of domain walls in ferroelectric thin films
,” Nat. Commun.
7
, 11630
(2016
).17.
M.
Schröder
,
A.
Haußmann
,
A.
Thiessen
,
E.
Soergel
,
T.
Woike
, and
L. M.
Eng
, “
Conducting domain walls in lithium niobate single crystals
,” Adv. Funct. Mater.
22
, 3936
(2012
).18.
G. F.
Nataf
,
M.
Guennou
,
J. M.
Gregg
,
D.
Meier
,
J.
Hlinka
,
E. K. H.
Salje
, and
J.
Kreisel
, “
Domain-wall engineering and topological defects in ferroelectric and ferroelastic materials
,” Nat. Rev. Phys.
2
, 634
(2020
).19.
S.-G.
Cao
,
H.-H.
Wu
,
H.
Ren
,
L.-Q.
Chen
,
J.
Wang
,
J. Y.
Li
, and
T.-Y.
Zhang
, “
A novel mechanism to reduce coercive field of ferroelectric materials via {111} twin engineering
,” Acta Mater.
97
, 404
(2015
).20.
S. S.
Behara
and
A. V.
der Ven
, “
Ferroelectric HfO2 and the importance of strain
,” Phys. Rev. Mater.
6
, 054403
(2022
).21.
Y. C.
Shu
,
J. H.
Yen
,
H. Z.
Chen
,
J. Y.
Li
, and
L. J.
Li
, “
Constrained modeling of domain patterns in rhombohedral ferroelectrics
,” Appl. Phys. Lett.
92
, 052909
(2008
).22.
J. S.
Meena
,
S. M.
Sze
,
U.
Chand
, and
T.-Y.
Tseng
, “
Overview of emerging nonvolatile memory technologies
,” Nanoscale Res. Lett.
9
, 526
(2014
).23.
T.
Mikolajick
,
U.
Schroeder
, and
S.
Slesazeck
, “
The past, the present, and the future of ferroelectric memories
,” IEEE Trans. Electron Dev.
67
, 1434
(2020
).24.
D.
Meier
,
J.
Seidel
,
A.
Cano
,
K.
Delaney
,
Y.
Kumagai
,
M.
Mostovoy
,
N. A.
Spaldin
,
R.
Ramesh
, and
M.
Fiebig
, “
Anisotropic conductance at improper ferroelectric domain walls
,” Nat. Mater.
11
, 284
(2012
).25.
T.
Rojac
,
A.
Bencan
,
G.
Drazic
,
N.
Sakamoto
,
H.
Ursic
,
B.
Jancar
,
G.
Tavcar
,
M.
Makarovic
,
J.
Walker
,
B.
Malic
, and
D.
Damjanovic
, “
Domain-wall conduction in ferroelectric BiFeO3 controlled by accumulation of charged defects
,” Nat. Mater.
16
, 322
(2017
).26.
P.
Sharma
,
A. N.
Morozovska
,
E. A.
Eliseev
,
Q.
Zhang
,
D.
Sando
,
N.
Valanoor
, and
J.
Seidel
, “
Specific conductivity of a ferroelectric domain wall
,” ACS Appl. Electron. Mater.
4
, 2739
(2022
).27.
A. K.
Yadav
,
C. T.
Nelson
,
S. L.
Hsu
,
Z.
Hong
,
J. D.
Clarkson
,
C. M.
Schlepütz
,
A. R.
Damodaran
,
P.
Shafer
,
E.
Arenholz
,
L. R.
Dedon
,
D.
Chen
,
A.
Vishwanath
,
A. M.
Minor
,
L. Q.
Chen
,
J. F.
Scott
,
L. W.
Martin
, and
R.
Ramesh
, “
Observation of polar vortices in oxide superlattices
,” Nature
530
, 198
(2016
).28.
J.
Ma
,
J.
Ma
,
Q. H.
Zhang
,
R. C.
Peng
,
J.
Wang
,
C.
Liu
,
M.
Wang
,
N.
Li
,
M. F.
Chen
,
X. X.
Cheng
,
P.
Gao
,
L.
Gu
,
L.-Q.
Chen
,
P.
Yu
,
J. X.
Zhang
, and
C.-W.
Nan
, “
Controllable conductive readout in self-assembled, topologically confined ferroelectric domain walls
,” Nat. Nanotechnol.
13
, 947
(2018
).29.
L. L.
Ding
,
Y.
Ji
,
X. Y.
Zhang
,
M. J.
Wu
,
Y.
Zheng
,
B.
Wang
, and
W. J.
Chen
, “
Exotic Quad-domain textures and transport characteristics of self-assembled BiFeO3 nanoislands on Nb-doped SrTiO3
,” ACS Appl. Mater. Interfaces
13
, 12331
(2021
).30.
V. Ya.
Shur
,
A. R.
Akhmatkhanov
, and
I. S.
Baturin
, “
Micro- and nano-domain engineering in lithium niobate
,” Appl. Phys. Rev.
2
, 040604
(2015
).31.
D. L.
Staebler
and
J. J.
Amodei
, “
Thermally fixed holograms in LiNbO3
,” Ferroelectrics
3
, 107
(1972
).32.
C.
Godau
,
T.
Kämpfe
,
A.
Thiessen
,
L. M.
Eng
, and
A.
Haußmann
, “
Enhancing the domain wall conductivity in lithium niobate single crystals
,” ACS Nano
11
, 4816
(2017
).33.
E.
Singh
,
H.
Beccard
,
Z. H.
Amber
,
J.
Ratzenberger
,
C. W.
Hicks
,
M.
Rüsing
, and
L. M.
Eng
, “
Tuning domain wall conductivity in bulk lithium niobate by uniaxial stress
,” Phys. Rev. B
106
, 144103
(2022
).34.
B.
Kirbus
,
C.
Godau
,
L.
Wehmeier
,
H.
Beccard
,
E.
Beyreuther
,
A.
Haußmann
, and
L. M.
Eng
, “
Real-time 3D imaging of nanoscale ferroelectric domain wall dynamics in lithium niobate single crystals under electric stimuli: Implications for domain-wall-based nanoelectronic devices
,” ACS Appl. Nano Mater.
2
(9
), 5787
–5794
(2019
).35.
T.
Otto
,
S.
Grafstroem
,
J.
Seidel
, and
L. M.
Eng
, “
Novel transparent electrodes for electro-optical near-field microscopy
,” Proc. SPIE
5122
, 369
(2003
).36.
E.
Beyreuther
,
J.
Ratzenberger
,
M.
Roeper
,
B.
Kirbus
,
M.
Rüsing
,
L. I.
Ivleva
, and
L. M.
Eng
, “
Photoconduction of polar and nonpolar cuts of undoped Sr0.61Ba0.39Nb2O6 single crystals
,” Crystals
11
, 780
(2021
).37.
M.
Zahn
,
E.
Beyreuther
,
I.
Kiseleva
,
A. S.
Lotfy
,
C. J.
McCluskey
,
J. R.
Maguire
,
A.
Suna
,
M.
Rüsing
,
J. M.
Gregg
, and
L. M.
Eng
, “
Equivalent-circuit model that quantitatively describes domain-wall conductivity in ferroelectric LiNbO3
,” Phys. Rev. Appl.
21
, 024007
(2024
).38.
S.
Hurskyy
,
U.
Yakhnevych
,
C.
Kofahl
,
E.
Tichy-Racs
,
H.
Schmidt
,
S.
Ganschow
,
H.
Fritze
, and
Y.
Suhak
, “
Electrical properties temperature stability Li-deficient near stoichiometric Li(Nb,Ta)O3 solid solutions up to 900 °C
,” Solid State Ionics
399
, 116285
(2023
).39.
P.
Reichenbach
,
T.
Kämpfe
,
A.
Haußmann
,
A.
Thiessen
,
T.
Woike
,
R.
Steudtner
,
L.
Kocsor
,
Z.
Szaller
,
L.
Kovács
, and
L. M.
Eng
, “
Polaron-mediated luminescence in lithium niobate and lithium tantalate and its domain contrast
,” Crystals
8
, 214
(2018
).40.
P.
Herth
,
T.
Granzow
,
D.
Schaniel
,
T.
Woike
,
M.
Imlau
, and
E.
Krätzig
, “
Evidence for light-induced hole polarons in LiNbO3
,” Phys. Rev. Lett.
95
, 067404
(2005
).© 2024 Author(s). Published under an exclusive license by AIP Publishing.
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