scholarly journals Tunable Non-Volatile Memory by Conductive Ferroelectric Domain Walls in Lithium Niobate Thin Films

Crystals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 804
Author(s):  
Thomas Kämpfe ◽  
Bo Wang ◽  
Alexander Haußmann ◽  
Long-Qing Chen ◽  
Lukas M. Eng
Keyword(s):  
Thin Film ◽  
Domain Wall ◽  
Lithium Niobate ◽  
Applied Voltage ◽  
Room Temperature ◽  
Domain Walls ◽  
Ferroelectric Domain ◽  
Stable Set ◽  
Non Volatile Memory ◽  
Binary Information

Ferroelectric domain wall conductance is a rapidly growing field. Thin-film lithium niobate, as in lithium niobate on insulators (LNOI), appears to be an ideal template, which is tuned by the inclination of the domain wall. Thus, the precise tuning of domain wall inclination with the applied voltage can be used in non-volatile memories, which store more than binary information. In this study, we present the realization of this concept for non-volatile memories. We obtain remarkably stable set voltages by the ferroelectric nature of the device as well as a very large increase in the conduction, by at least five orders of magnitude at room temperature. Furthermore, the device conductance can be reproducibly tuned over at least two orders of magnitude. The observed domain wall (DW) conductance tunability by the applied voltage can be correlated with phase-field simulated DW inclination evolution upon poling. Furthermore, evidence for polaron-based conduction is given.

scholarly journals Charged Domain Wall and Polar Vortex Topologiesin a Room Temperature Magnetoelectric Multiferroic Thin Film

2021 ◽  
Author(s):  
Kalani Moore ◽  
Eoghan O'Connell ◽  
Lynette Keeney ◽  
Clive Downing ◽  
Michael Schmidt ◽  
...  
Keyword(s):  
Thin Film ◽  
Domain Wall ◽  
Room Temperature ◽  
Domain Walls ◽  
Strain Engineering ◽  
Unit Cell ◽  
Tail Domain ◽  
Aurivillius Phase ◽  
Topological Features ◽  
Dielectric Layers

Abstract Multiferroic domain walls are an emerging solution for future low-power nanoelectronics due to their combined tuneable functionality and mobility. Here we show that the magnetoelectric multiferroic Aurivillius phase Bi6TixFeyMnzO18 (B6TFMO) crystal is an ideal platform for domain wall-based nanoelectronic devices. The unit cell of B6TFMO is distinctive as it consists of a multiferroic layer between dielectric layers. We utilise atomic resolution scanning transmission electron microscopy and spectroscopy to map the sub-unit-cell polarisation in B6TFMO thin films. 180˚ charged head-to-head and tail-to-tail domain walls are found to pass through > 8 ferroelectric-dielectric layers of the film. They are structurally similar to BiFeO3 DWs but contain a large surface charge density (σ_s) = 1.09 |e|per perovskite cell, where |e| is elementary charge. Although polarisation is primarily in-plane, c-axis polarisation is identified at head-to-tail domain walls with an associated electromechanical coupling of strain and polarisation. Finally, we reveal that with controlled strain engineering during thin film growth, room-temperature vortexes are formed in the ferroelectric layer. These results confirm that sub-unit-cell topological features can play an important role in controlling the conduction properties and magnetisation state of Aurivillius phase films and other multiferroic heterostructures.

Long-range strains and the effects of applied field at 180° ferroelectric domain walls in lithium niobate

2004 ◽  
Vol 69 (6) ◽  
Author(s):  
Terrence Jach ◽  
Sungwon Kim ◽  
Venkatraman Gopalan ◽  
Stephen Durbin ◽  
David Bright
Keyword(s):  
Lithium Niobate ◽  
Long Range ◽  
Applied Field ◽  
Domain Walls ◽  
Ferroelectric Domain

Ferroelectric domain-wall logic units

2021 ◽  
Author(s):  
Jing Wang ◽  
Jing Ma ◽  
Houbing Huang ◽  
Ji Ma ◽  
Hasnain Jafri ◽  
...  
Keyword(s):  
Domain Wall ◽  
Electric Field ◽  
Domain Walls ◽  
Logic Gates ◽  
Piezoresponse Force Microscopy ◽  
Ferroelectric Domain ◽  
Conduction Path ◽  
Conductive Atomic Force Microscopy ◽  
Flexible Control ◽  
Force Microscopy

Abstract The electronic conductivities of ferroelectric domain walls have been extensively explored over the past decade for potential nanoelectronic applications. However, the realization of logic devices based on ferroelectric domain walls requires reliable and flexible control of the domain-wall configuration and conduction path. Here, we demonstrate electric-field-controlled stable and repeatable on-and-off switching of conductive domain walls within topologically confined vertex domains naturally formed in self-assembled ferroelectric nano-islands. Using a combination of piezoresponse force microscopy, conductive atomic force microscopy, and phase-field simulations, we show that on-off switching is accomplished through reversible transformations between charged and neutral domain walls via electric-field-controlled domain-wall reconfiguration. By analogy to logic processing, we propose programmable logic gates (such as NOT, OR, AND and their derivatives) and logic circuits (such as fan-out) based on reconfigurable conductive domain walls. Our work provides a potentially viable platform for programmable all-electric logic based on a ferroelectric domain-wall network with low energy consumption.

scholarly journals Ferroelectric Domain Walls in PbTiO3 Are Effective Regulators of Heat Flow at Room Temperature

Nano Letters ◽  
2019 ◽  
Vol 19 (11) ◽  
pp. 7901-7907 ◽  
Author(s):  
Eric Langenberg ◽  
Dipanjan Saha ◽  
Megan E. Holtz ◽  
Jian-Jun Wang ◽  
David Bugallo ◽  
...  
Keyword(s):  
Heat Flow ◽  
Room Temperature ◽  
Domain Walls ◽  
Ferroelectric Domain

Room temperature concurrent formation of ultra-dense arrays of ferroelectric domain walls

2015 ◽  
Vol 107 (14) ◽  
pp. 142903 ◽  
Author(s):  
Mahamudu Mtebwa ◽  
Ludwig Feigl ◽  
Petr Yudin ◽  
Leo J. McGilly ◽  
Konstantin Shapovalov ◽  
...  
Keyword(s):  
Room Temperature ◽  
Domain Walls ◽  
Ferroelectric Domain ◽  
Dense Arrays

scholarly journals Charged Domain Wall and Polar Vortex Topologies in a Room Temperature Magnetoelectric Multiferroic Thin Film

2021 ◽  
Author(s):  
Kalani Moore ◽  
Eoghan O'Connell ◽  
Sinéad M. Griffin ◽  
Clive Downing ◽  
Louise Colfer ◽  
...  
Keyword(s):  
Thin Film ◽  
Domain Wall ◽  
Room Temperature ◽  
Polar Vortex ◽  
Strain Engineering ◽  
Unit Cell ◽  
Electrostatic Energy ◽  
Tail Domain ◽  
Aurivillius Phase ◽  
Topological Features

Abstract Multiferroic topologies are an emerging solution for future low-power magnetic nanoelectronics due to their combined tuneable functionality and mobility. Here, we show that in addition to being magnetoelectric multiferroic at room temperature, thin film Aurivillius phase Bi6TixFeyMnzO18 is an ideal material platform for both domain wall and vortex topology based nanoelectronic devices. Utilising atomic resolution electron microscopy, we reveal the presence and structure of 180˚ type charged head-to-head and tail-to-tail domain walls passing throughout the thin film. Theoretical calculations confirm the sub-unit cell cation site preference and charged domain wall energetics for Bi6TixFeyMnzO18. Finally, we show that polar vortex type topologies also form at out-of-phase boundaries of stacking faults when internal strain and electrostatic energy gradients are altered. This study could pave the way for controlled polar vortex topology formation via strain engineering in other multiferroic thin films. Moreover, these results confirm the sub-unit-cell topological features play an important role in controlling the charge and spin state of Aurivillius phase films and other multiferroic heterostructures.

Magnetoresistance of Nanoscale Domain Walls Formed in Arrays of Parallel Nanowires

SPIN ◽  
2019 ◽  
Vol 09 (01) ◽  
pp. 1950004
Author(s):  
Jingchun Wang ◽  
Floriano Cuccureddu ◽  
Rafael Ramos ◽  
Cormac Ó. Coileáin ◽  
Igor V. Shvets ◽  
...  
Keyword(s):  
Thin Films ◽  
Domain Wall ◽  
Exchange Interaction ◽  
Exchange Bias ◽  
Room Temperature ◽  
Domain Walls ◽  
Nanowire Array ◽  
Bias Field ◽  
Nanowire Arrays ◽  
Exchange Bias Field

We present the possibility of enhancing magnetoresistance (MR) by controlling nanoscale domain wall (DW) width in a planar nanowire array. Results based on micromagnetic calculations show that DW width decreases with increasing exchange bias field and decreases with reducing exchange interaction between neighboring nanowires. Fe/Fe3O4 nanowire arrays were grown on [Formula: see text]-plane sapphire to demonstrate the feasibility of this concept, and an enhanced MR ratio of 3.7% was observed at room temperature. compared with flat and stepped Fe3O4 thin films.

scholarly journals Calibration of material parameters based on 180$$^\circ $$ and 90$$^\circ $$ ferroelectric domain wall properties in Ginzburg–Landau–Devonshire phase field models

2020 ◽  
Vol 90 (12) ◽  
pp. 2755-2774
Author(s):  
Moritz Flaschel ◽  
Laura De Lorenzis
Keyword(s):  
Domain Wall ◽  
Phase Field ◽  
Domain Walls ◽  
Ferroelectric Domain ◽  
Ginzburg Landau ◽  
Closed Form Solutions ◽  
Material Parameters ◽  
Phase Field Models ◽  
Mobility Parameter ◽  
The Relationship

Abstract Ferroelectric phase field models based on the Ginzburg–Landau–Devonshire theory are characterized by a large number of material parameters with problematic physical interpretation. In this study, we systematically address the relationship between these parameters and the main properties of ferroelectric domain walls. A variational approach is used to derive closed form solutions for the polarization fields at the phase transition regions as well as for the propagation velocities of the domain walls. Introducing a modified set of material parameters, which appropriately scales different contributions to the free energy, we are able to accurately calibrate these parameters based on domain wall thickness and energy of both 180$$^\circ $$ ∘ and 90$$^\circ $$ ∘ domain walls. Moreover, the mobility parameter appearing in the Ginzburg–Landau evolution equation can be accurately calibrated based on the propagation velocity of the domain walls.

Application of electron holography to ferroelectric study

1993 ◽  
Vol 51 ◽  
pp. 1092-1093
Author(s):  
X. Zhang ◽  
D. C. Joy ◽  
L. F. Allard ◽  
T. A. Nolan
Keyword(s):  
Domain Wall ◽  
Domain Walls ◽  
Ferroelectric Domain ◽  
Electron Holography ◽  
Local Domain ◽  
Holographic Method ◽  
Wall Area ◽  
Weak Phase ◽  
Wall Structures ◽  
Essential Input

With the development of FE TEM, electron holography becomes a reality to materials scientists, which opens a new window for materials study. Weak phase objects, such as a thin transparent specimen or an electric or a magnetic field, which have little or no effect on the intensity of the transmitted wave, can readily be observed via holography because of the phase shift that they produce. Application of the electron holographic method has been extended to the study of ferroelectric domain wall structures. This work presents the most recent results in this area.Polarization gradients within domain walls are extremely important for the understanding of the extrinsic elastio-dielectric properties of ferroelectrics. Electron holographic studies of the local domain wall profiles provide essential input parameters for phenomenological theories of domain structure and of the macroscopic properties derived from the theories. Figure 1(a) is an electron hologram of the ferroelectric (BaTiO3) 90° domain wall area.

Sign in / Sign up

Export Citation Format

Share Document