Article
Materials Science, Multidisciplinary
Duk-Hyun Choe, Sunghyun Kim, Taehwan Moon, Sanghyun Jo, Hagyoul Bae, Seung-Geol Nam, Yun Seong Lee, Jinseong Heo
Summary: A new topological class of domain walls in orthorhombic HfO2 was discovered, revealing an atomic-scale mechanism of polarization switching with unexpectedly low energy barriers of domain wall motion. This challenges previous beliefs and provides a strategy to reduce coercive fields in HfO2-based ferroelectric devices.
Article
Nanoscience & Nanotechnology
Yoonho Ahn, Jong Yeog Son
Summary: The ferroelectric domain switching kinetics of PbTiO3 nanostructures were investigated, showing faster domain switching behavior and lower activation energy compared to PbTiO3 thin film. This insight could be applied to highly integrated and fast ferroelectric random access memory applications.
SCRIPTA MATERIALIA
(2021)
Article
Engineering, Electrical & Electronic
Dong Hyun Lee, Geun Hyeong Park, Se Hyun Kim, Kun Yang, Jaewook Lee, Hyojun Choi, Younghwan Lee, Jin Ju Ryu, Je In Lee, Gun Hwan Kim, Min Hyuk Park
Summary: This study investigated the effects of different electrode materials on the properties of ferroelectric HZO films. The results showed that the Mo electrode reduced device-to-device variation, while the W and TiN electrodes were beneficial for achieving high-speed operations.
IEEE ELECTRON DEVICE LETTERS
(2023)
Article
Materials Science, Multidisciplinary
E. Paramonova, V. S. Bystrov, X. Meng, H. Shen, J. Wang, V. M. Fridkin
Summary: The article discusses the polarization switching kinetics of ferroelectric crystals and the transition between homogeneous and domain switching in nanoscale ferroelectric films. According to the Ginzburg-Landau-Devonshire (LGD) theory, homogeneous switching is only possible in two-dimensional ferroelectrics. Experimental results and first-principle calculations confirm the transition region from homogeneous to domain switching, with fitting done using sigmoidal Boltzmann functions.
Article
Materials Science, Ceramics
J. Roscow, Y. Li, D. A. Hall
Summary: The relationship between residual stress and domain switching in porous barium titanate ceramics was investigated using synchrotron X-ray diffraction. It was found that ceramics manufactured by freeze casting with higher pore fraction exhibited a higher domain switching fraction at a higher electric field, attributed to a reduction in residual stress. However, the contribution of intrinsic lattice strain to the piezoelectric properties was slightly reduced in the freeze cast ceramics compared to conventionally processed ceramics.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Yurii Tikhonov, Jesi R. Maguire, Conor J. McCluskey, James P. McConville, Amit Kumar, Haidong Lu, Dennis Meier, Anna Razumnaya, John Martin Gregg, Alexei Gruverman, Valerii M. Vinokur, Igor Luk'yanchuk
Summary: Ferroelectric domain walls play an important role in novel materials physics, where polarization discontinuities often lead to emergent 2D conductivity. In multiaxial ferroelectrics, complex topological patterns can ameliorate such discontinuities, while in uniaxial ferroelectrics, discontinuities are assumed to be unavoidable. However, experimental and theoretical investigations on lead germanate reveal that polar discontinuities can be obviated by mutual domain bifurcation along different axes, creating a characteristic saddle-point domain wall morphology and associated novel dipolar topology.
ADVANCED MATERIALS
(2022)
Article
Materials Science, Ceramics
Yang Yin, Yucheng Tang, Wenyuan Pan, Aizhen Song, Jingru Yu, Boping Zhang
Summary: Research has shown that nonergodic relaxor ferroelectrics near the morphotropic phase boundary are favorable for enhancing the piezoelectric and electrostrain properties of materials, thereby reducing the energy barrier for polarization rotation.
CERAMICS INTERNATIONAL
(2021)
Article
Multidisciplinary Sciences
V. Sebastian Calderon, John Hayden, Steven M. Baksa, William Tzou, Susan Trolier-McKinstry, Ismaila Dabo, Jon -Paul Maria, Elizabeth C. Dickey
Summary: Ferroelectric wurtzites have the potential to revolutionize modern microelectronics. This study observed and quantified real-time polarization switching of ferroelectric wurtzite at the atomic scale. A polarization reversal model was proposed, providing an important first step for property engineering efforts.
Article
Physics, Multidisciplinary
Ji Hye Lee, Hong Joon Kim, Jiyong Yoon, Sanghyeon Kim, Jeong Rae Kim, Wei Peng, Se Young Park, Tae Won Noh, Daesu Lee
Summary: This research reveals a method of mechanical polarization switching utilizing metastable ferroelectricity, and confirms that mechanical forces can significantly reduce the coercivity of metastable ferroelectricity, enabling efficient polarization switching. Furthermore, using low mechanical forces allows for higher density data storage.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Applied
Minh-Tien Le, Le Van Lich, Takahiro Shimada, Takayuki Kitamura, Giang Trong Nguyen, Van-Hai Dinh
Summary: The development of modern thin-film deposition methods has enabled the design and fabrication of new materials, with a focus on compositionally graded ferroelectric/ferromagnetic multilayer thin films. By utilizing a phase-field model based on Ginzburg-Landau theory, researchers have studied the material properties and magnetoelectric (ME) coupling of graded Pb(1-x)SrxTiO3/CoFe2O4 laminated nanocomposites, finding that the ME effect is strongly influenced by the composition gradient.
APPLIED PHYSICS LETTERS
(2021)
Article
Chemistry, Physical
Andre Marino Goncalves, Rolando Placeres Jimenez, Jose Antonio Eiras
Summary: This study investigated the role of domain structure and relative domain-electric field orientations in the polarization reorientation process in polycrystalline ferroelectric thin films by combining macroscopic and nanoscopic analyses. The results show that the relative polarization orientation of the domains significantly impacts the reorientation process, affecting the stability and efficiency of polarization switching. Through a phenomenological model, macroscopic parameters related to the polarization reorientation, domain structure, and domain wall mobility were obtained, allowing for a better understanding and explanation of the observed responses.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Materials Science, Multidisciplinary
Lee A. Griffin, Samuel Williams, Shujun Zhang, Nazanin Bassiri-Gharb
Summary: The vibration and motion of domain walls play a significant role in the response of ferroelectric materials, but the specific length scales at which they impact characteristic parameters remain largely unexplored. Proximity to domain walls has limited impact on polarization switching for locations less than or similar to 300 nm away. The results are consistent with the presence of chemical, polar, and structural heterogeneities in relaxor-ferroelectrics and their soft piezoelectric behavior.
PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE
(2021)
Article
Materials Science, Multidisciplinary
Laurent Guin, Dennis M. Kochmann
Summary: When subjected to electro-mechanical loading, ferroelectrics evolve their polarization through the nucleation and evolution of domains. Existing phase-field models assume linear kinetics for domain wall evolution, while experiments indicate that domain wall kinetics is actually nonlinear. We propose a new multiple-phase-field model that allows for nonlinear domain wall motion and can be applied to other solid-solid phase transformation problems.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2023)
Article
Materials Science, Multidisciplinary
Urko Petralanda, Thomas Olsen
Summary: This work presents a detailed characterization of domain walls (DWs) in two-dimensional ferroelectric materials GeS, GeSe, SnS and SnSe, and proposes a method for calculating coercive fields based on DW migration. The calculated coercive fields show good agreement with experimental results and are two orders of magnitude smaller than those predicted by coherent monodomain switching. In addition, the study finds that the presence of 180° DWs leads to a red shift in the absorption spectrum, suggesting that optical probes can be used to determine the density of DWs.
Article
Materials Science, Multidisciplinary
M. Srinivasagan, K. Jayabal
Summary: This study presents a micromechanical model based on a Voronoi-based discretization method for polycrystalline ferroelectrics. It successfully simulates the complex nonlinear hysteretic behavior and polarization rotations under various electromechanical loads and compares well with experimental observations.
MECHANICS OF ADVANCED MATERIALS AND STRUCTURES
(2023)
Article
Multidisciplinary Sciences
E. Kirichenko, V. A. Stephanovich
Summary: The study found that the synergy between screening and disorder can either destroy excitons or promote the creation of bound states, with energy level crossings occurring at certain discrete values of the screening radius. These effects may be related to quantum manifestations of chaotic exciton behavior in 2D semiconductor structures.
SCIENTIFIC REPORTS
(2021)
Article
Multidisciplinary Sciences
V. A. Stephanovich, W. Olchawa
Summary: This study theoretically investigates the properties of a soliton solution of the fractional Schrodinger equation with quintic nonlinearity. The study shows that by substituting the ordinary Laplacian with its fractional counterpart, the soliton texture can be stabilized. Furthermore, the study finds that the fractional Schrodinger equation with quintic nonlinearity allows for the existence of stable soliton textures within a specific range.
SCIENTIFIC REPORTS
(2022)
Article
Physics, Multidisciplinary
Piotr Garbaczewski, Vladimir A. Stephanovich, Grzegorz Engel
Summary: This paper proposes a method for calculating electronic spectra in ordered and disordered semiconductor structures and discusses the relationship between the electron spectrum and the shape of the QW in such structures. This is significant for high-end electronics, flexible electronics, spintronics, optoelectronics, and energy harvesting applications.
NEW JOURNAL OF PHYSICS
(2022)
Article
Multidisciplinary Sciences
V. A. Stephanovich, E. Kirichenko, V. K. Dugaev, Jackie Harjani Sauco, Belen Lopez Brito
Summary: This article studies the role of disorder in the vibration spectra of molecules and atoms in solids and describes it using a fractional generalization of the quantum-mechanical oscillator problem. The study shows that in the fractional 3D oscillator problem, the orbital momentum degeneracy is lifted and the energy starts to depend on orbital quantum number l. These findings have significant implications for the physical properties of various solids, including multiferroics and oxide heterostructures.
SCIENTIFIC REPORTS
(2022)
Article
Multidisciplinary Sciences
V. A. Stephanovich, W. Olchawa, E. Kirichenko, V. K. Dugaev
Summary: In this study, we examine the properties of a soliton solution of the fractional Schrödinger equation with cubic-quintic nonlinearity. We have shown that the substitution of the ordinary Laplacian in the Schrödinger equation by its fractional counterpart can stabilize the soliton texture. By studying the dependence of soliton frequency and norm, we determine the existence and stability regions of the fractional soliton solution. The simple variational approach combined with the VK criterion provides reliable information about soliton structure and stability.
SCIENTIFIC REPORTS
(2022)
Article
Physics, Fluids & Plasmas
V. A. Stephanovich, W. Olchawa, E. V. Kirichenko
Summary: We investigate the influence of disorder and screening on excitons in semiconductors, such as polymeric semiconductors and van der Waals structures. We phenomenologically consider disorder using the fractional Schrodinger equation in the screened hydrogenic problem. Our main findings suggest that screening and disorder together can either destroy or enhance excitons in the semiconductor, potentially leading to their collapse in extreme cases. These effects could be relevant for understanding chaotic exciton behavior and should be taken into account in device applications where dielectric screening and disorder play important roles. Our theoretical results provide insights into the excitonic properties in semiconductors with different degrees of disorder and Coulomb interaction screenings.
Article
Materials Science, Multidisciplinary
V. A. Stephanovich, E. V. Kirichenko, G. Engel, V. K. Dugaev
Summary: We calculate the Ruderman-Kittel-Kasuya-Yosida interaction between impurity spins localized at the surface of an imperfect topological insulator (TI) and show that the warping and tilting of a TI Dirac cone result in a highly anisotropic response to localized spin rotation. The Friedel oscillation strength of the imperfect TI depends on the direction in its plane, which can serve as a fingerprint of the initial Dirac cone distortion. The interplay of spin-orbit interaction, warping and tilting of the initial Dirac cone, and the indirect exchange between localized impurities leads to unusual dynamics.
Article
Physics, Multidisciplinary
Piotr Garbaczewski, Vladimir A. Stephanovich
Summary: This article investigates the relaxation properties of the Smoluchowski diffusion process on a line with a confining potential. The author quantifies these properties using the Schrodinger semi-group and develops a computer-assisted procedure to approximate the spectral solution. Overall, the article explores the spectral properties of the diffusion process and provides insights into its relaxation behavior.
ACTA PHYSICA POLONICA B
(2022)
Article
Materials Science, Multidisciplinary
V. A. Stephanovich, E. Kirichenko, V. K. Dugaev, J. Barnas
Summary: We theoretically study the dynamic Friedel oscillations of electrons at the surface of a topological insulator (TI) generated by the rotation of a localized impurity spin. Our research shows that the anisotropic response to the localized spin rotation is caused by the spin-orbit interaction in Rashba form. Additionally, the dynamic spin moment emitted by the localized dynamical spin depends on the orientation in the TI plane. This research provides a basis for manipulating spin transport in topological insulators with localized impurity spins.
Article
Materials Science, Multidisciplinary
V. A. Stephanovich, E. Kirichenko, G. Engel, Yu G. Semenov, K. W. Kim
Summary: Theoretical analysis reveals that magnetic ions randomly distributed in a 2D semiconductor system can generate ferromagnetic long-range order. The discrete symmetry of the 2D Ising model of spin-spin interaction is crucial in this phenomenon, and fluctuations in molecular field play a key role in achieving ferromagnetism. The proposed theoretical model describes magnetization and phase transition temperature in terms of a single parameter, the chemical potential, and suggests a pathway to achieve high T-c and control magnetic properties externally.
Article
Physics, Multidisciplinary
Tinggui Chen, Baizhan Xia, Dejie Yu, Chuanxing Bi
Summary: This study proposes a gradient phononic crystal structure for enhanced acoustic sensing. By breaking the symmetry of the PC structure, topologically protected edge states are introduced, resulting in topological acoustic rainbow trapping. The robustness and enhancement properties are verified numerically and experimentally.
