Article
Physics, Applied
Amanda Huon, Sangmoon Yoon, Michael R. Fitzsimmons, Timothy R. Charlton, Jong Mok Ok, Clarina dela Cruz, Ho Nyung Lee
Summary: Epitaxial SrRu1-xSnxO3 thin films were deposited on SrTiO3 substrates using pulsed laser deposition, showing good crystalline quality and smooth surface. Sn doping can tune chemical pressure and magnetism, leading to an increase in resistivity and decrease in ferromagnetism of the films.
APPLIED PHYSICS LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Anusha Kamath Manjeshwar, Sreejith Nair, Anil Kumar Rajapitamahuni, Richard D. James, Bharat Jalan
Summary: Controlling defect densities in SrRuO3 films is crucial for investigating the relationship between its structural, electrical, and magnetic properties. By combining film growth, electrical transport, and magnetometry, we demonstrate the adsorption-controlled growth of phase-pure, epitaxial, and stoichiometric SrRuO3 films on SrTiO3 (001) substrates. It is found that the anomalous Hall curves arise from two distinct magnetic domains and a high residual resistivity ratio is achieved in a coherently strained SrRuO3 film.
Article
Chemistry, Multidisciplinary
Yuning Wang, Yipu Qu, Yu Xu, Didi Li, Zhengqian Lu, Jianjie Li, Xujun Su, Guobin Wang, Lin Shi, Xionghui Zeng, Jianfeng Wang, Bing Cao, Ke Xu
Summary: Remote epitaxy (RE) is a prospective universal growth strategy that utilizes the penetration of substrate polarity through two-dimensional materials (2DMs) to act on the epi-layer. However, the role of 2DMs in RE has not been deeply investigated. This study realizes the RE of single-crystal films on the weakest polarity/iconicity substrate and reveals its essence physical properties.
Article
Materials Science, Multidisciplinary
K. Jenni, S. Kunkemoeller, A. Tewari, R. A. Ewings, Y. Sidis, A. Schneidewind, P. Steffens, A. A. Nugroho, M. Braden
Summary: The magnetic excitations in ferromagnetic SrRuO3 were investigated using inelastic neutron scattering experiments on triple-axis and time-of-flight spectrometers. The low-energy low-temperature response exhibited a quadratic spin-wave dispersion with an anisotropy gap. The magnon dispersion extended up to 35 meV, with no evidence of a continuum of Stoner excitations below this energy. However, the magnon response weakened at higher energies. In addition to the anomalous softening of the spin-wave stiffness and gap induced by the topology of the Bloch states, the magnon excitations also showed broadening in energy, which increased with temperature.
Article
Physics, Multidisciplinary
Jing-Xian Zhang, Ming-Rui Bao, Fei Ye, Jia Liu, Long Cheng, Xiao-Fang Zhai
Summary: SrRuO3 (SRO) has unique itinerate ferromagnetism and unusual electrical transport properties. The growth and quality of SRO thin films are affected by factors such as laser energy density, substrate temperature, and target surface conditions. The topological Hall effect (THE) in SRO is influenced by these factors. The SRO thin film grown under the optimal conditions exhibits the optimal conductivity and the strongest THE.
ACTA PHYSICA SINICA
(2023)
Review
Chemistry, Multidisciplinary
Seung Gyo Jeong, Jin Young Oh, Lin Hao, Jian Liu, Woo Seok Choi
Summary: Unexpected and useful functionalities arise when different materials merge coherently. This review focuses on artificial oxide superlattices, specifically 4d and 5d perovskite oxide superlattices, which exhibit controllable correlated quantum phenomena due to their unique atomic and crystal structures. The review discusses various modulations and controls in crystal structures, electronic and magnetic properties, and integration of topology and correlation in these superlattices. It provides insights into the deliberate design of superlattice structures to achieve novel functionalities.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Zhangzhang Cui, Yingying Zhang, Xiaofang Zhai, Hanghui Chen, Yi-De Chuang, Jinghua Guo, Zhengping Fu, Zhengcao Li, Yalin Lu
Summary: Most observed phase separation phenomena in complex oxides occur in systems with chemical dopants or structural defects. However, recent experiments have shown that phase separation can be suppressed in clean systems without chemical disorders. In this study, chemically ordered hybrid superlattices were used to demonstrate phase separation without the need of chemical dopants or structural defects. The findings suggest that phase separation can exist in clean systems and provide an alternative pathway to introduce phase separation in correlated oxides.
Article
Chemistry, Multidisciplinary
Jonathan R. Chin, Marshall B. Frye, Derrick Shao-Heng Liu, Maria Hilse, Ian C. Graham, Jeffrey Shallenberger, Ke Wang, Roman Engel-Herbert, Mengyi Wang, Yun Kyung Shin, Nadire Nayir, Adri C. T. van Duin, Lauren M. Garten
Summary: Self-limiting stoichiometry promotes the growth of SnSe thin films by maintaining film stoichiometry and controlling crystallographic orientation. Results show that self-limiting stoichiometry can increase the lateral scale of SnSe layers, providing a promising avenue for device fabrication.
Article
Chemistry, Multidisciplinary
Chang Jae Roh, Eun Kyo Ko, Yunyeong Chang, Soon Hee Park, Junsik Mun, Miyoung Kim, Tae Won Noh
Summary: Cracks have a significant impact on the physical properties of materials, including structural stability, electrical conductivity, and thermal conductivity. This study comprehensively investigates the effect of nanocracks on the physical properties of metallic SrRuO3 (SRO) thin films. It is found that the presence of nanocracks leads to inhomogeneous relaxation of strain in the SRO layer, resulting in its dc conductivity approaching zero. Additionally, an enhancement of the local optical conductivity near the nanocrack region is observed, which is attributed to the strain relaxation near the nanocracks. This research suggests that nanocracks can be utilized as promising platforms for investigating local emergent phenomena related to strain effects.
Article
Multidisciplinary Sciences
M. Pendharkar, B. Zhang, H. Wu, A. Zarassi, P. Zhang, C. P. Dempsey, J. S. Lee, S. D. Harrington, G. Badawy, S. Gazibegovic, R. L. M. Op het Veld, M. Rossi, J. Jung, A-H Chen, M. A. Verheijen, M. Hocevar, E. P. A. M. Bakkers, C. J. Palmstrom, S. M. Frolov
Summary: By coating semiconductor indium antimonide nanowires with tin shells, researchers were able to prepare tunnel junctions without interdiffusion at the interface. A 15-nanometer-thick tin shell induced a hard superconducting gap, allowing superconductivity to persist in magnetic fields up to 4 teslas. These findings suggest a more flexible approach to fabricating superconducting and topological quantum circuits.
Article
Chemistry, Multidisciplinary
Zhixiong Deng, Junhua Liu, Yuhao Hong, Long Wei, Shilin Hu, Wen Xiao, Lin Li, Lingfei Wang, Kai Chen, Zhaoliang Liao
Summary: This paper demonstrates the persistent layer-by-layer growth of SrRuO3 thin films by regulating the growth conditions, achieving precise control of the thickness and construction of superlattices. By constructing SRO/STO superlattices, a quasi-2D ferromagnetic monolayer film is achieved. These results pave a path towards the synthesis of SRO heterostructures and properties control at an atomic scale.
ADVANCED MATERIALS INTERFACES
(2022)
Article
Materials Science, Multidisciplinary
Prahald Siwakoti, Zhen Wang, Mohammad Saghayezhian, David Howe, Zeeshan Ali, Yimei Zhu, Jiandi Zhang
Summary: The lattice structure of SrRuO3 thin films can differ significantly from that of the corresponding bulk material, with RuO6 distortions appearing even in single unit cell films. Thicker films require 3-4 unit cells to fully relax to a bulklike orthorhombic structure. The TiO6 octahedra of the substrate near the interface with SrRuO3 films remain undistorted, unlike those near CaRuO3 film interfaces.
PHYSICAL REVIEW MATERIALS
(2021)
Article
Materials Science, Coatings & Films
Chengyang Zhang, Ravindra Singh Bisht, Amin Nozariasbmarz, Arnob Saha, Chan Su Han, Qi Wang, Yifan Yuan, Abhronil Sengupta, Shashank Priya, Shriram Ramanathan
Summary: VO2 thin films were successfully grown on different substrates and their crystal structure and chemical composition were analyzed using X-ray diffraction and X-ray photoelectron spectroscopy. The films exhibited metal-insulator transition under temperature and electric field, which is of great importance for the application of phase transition devices.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
(2022)
Article
Multidisciplinary Sciences
Yoshiharu Suzuki
Summary: Water can form two different amorphs and undergo a reversible polyamorphic transition with the change in pressure. It has been observed that the reversible liquid-liquid transition between low-density liquid and high-density liquid is a first-order transition.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Chemistry, Multidisciplinary
Weinan Lin, Liang Liu, Qing Liu, Lei Li, Xinyu Shu, Changjian Li, Qidong Xie, Peiheng Jiang, Xuan Zheng, Rui Guo, Zhishiuh Lim, Shengwei Zeng, Guowei Zhou, Han Wang, Jing Zhou, Ping Yang, Ariando, Stephen J. Pennycook, Xiaohong Xu, Zhicheng Zhong, Zhiming Wang, Jingsheng Chen
Summary: Magnetic Weyl fermions originate from TRS-breaking in magnetic crystalline structures and can be effectively controlled by electric and magnetic fields. Electric field control of magnetic Weyl fermions has been demonstrated in SrRuO3 (111) thin films, showing promise for energy-efficient electronics. This work may stimulate further research on and manipulation of Weyl fermions in other magnetic materials.
ADVANCED MATERIALS
(2021)
Article
Chemistry, Physical
Huan Tan, Jike Lyu, Yunwei Sheng, Pamela Machado, Tingfeng Song, Akash Bhatnagar, Mariona Coll, Florencio Sanchez, Josep Fontcuberta, Ignasi Fina
Summary: Piezoelectric force microscopy (PFM) is a powerful tool to study ferroelectric materials, but extrinsic effects from surface charges often complicate the data interpretation. In this study, we determined the compensating voltage for different ferroelectric materials by comparing with the corresponding I-V characteristics. We found that the asymmetry of the I-V characteristics is related to the sign and magnitude of the bias voltage required to compensate for surface charges.
APPLIED SURFACE SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Tingfeng Song, Romain Bachelet, Guillaume Saint-Girons, Ignasi Fina, Florencio Sanchez
Summary: By using an ultrathin seed layer, high-quality epitaxial films of orthorhombic Hf0.5Zr0.5O2 can be obtained at a lower temperature, and they exhibit enhanced endurance.
Article
Physics, Applied
Yunwei Sheng, Mathieu Mirjolet, Mario Villa, Jaume Gazquez, Jose Santiso, Andreas Klein, Jordi Fraxedas, Josep Fontcuberta
Summary: Epitaxial LaFeO3-based photocells with different thicknesses were grown on LSAT single-crystal substrates, using LSMO and Pt/BLSO electrodes, to determine their photoresponse. The short-circuit photocurrent initially increases and then decreases with LFO thickness, and is larger or smaller with Pt or BLSO electrodes. The open-circuit voltage shows the opposite trend, being smaller or larger with Pt and BLSO, respectively, consistent with the electronic band alignments and rectifying character of the dark current-voltage data. The complex microstructure and grain boundaries of the films play a significant role in the observed responsivity, which is larger than in similar LFO-based structures.
PHYSICAL REVIEW APPLIED
(2023)
Article
Physics, Applied
J. W. Adkins, I. Fina, F. Sanchez, S. R. Bakaul, J. T. Abiade
Summary: In this study, the influence of controllable polarization reversal and built-in electric fields on pyroelectric and electrocaloric effects in a BaTiO3 thin film is examined using a modified indirect method. It is found that the magnitude of the sample's change in polarization with temperature is sensitive to the degree of polarization reversal. The pyroelectric response is small at low fractions of switched polarization and grows larger with higher fractions of reversal. This is attributed to the destabilizing effect of the internal built-in field on low fractions of switched polarization.
APPLIED PHYSICS LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Alexandre Silva, Ignasi Fina, Florencio Sanchez, Jose P. B. Silva, Luis Marques, Veniero Lenzi
Summary: We investigated the influence of La content on the structural and ferroelectric properties of epitaxial HfO2 films. It was found that 2-5 at. % La-doped HfO2 films exhibit optimum remanent polarization and reduced coercive field. Density functional theory calculations supported the experimental results and revealed that the polarization switching in epitaxial La:HfO2 films can be understood based on the synergetic contribution of a non-ferroelectric monoclinic phase and La doping itself.
MATERIALS TODAY PHYSICS
(2023)
Article
Chemistry, Physical
Vishal Sharma, Inderpal Singh, Sunil K. Arora, Florencio Sanchez, Fouran Singh, Shilpa Tripathi, S. N. Jha
Summary: We investigated the impact of Ag15+ (200 MeV) ion irradiation on the surface electronic structure of epitaxial LaNiO3 films on (100) oriented LaAlO3 substrates by analyzing La (4d to 4f) and Ni (3p to 3d) photoemission transitions. Results showed slight enhancement in the spectral features for La (4d to 4f) transitions, but no enhancement for Ni (3p to 3d) transitions in both pristine and irradiated samples. Changes in constant initial state (CIS) spectra for La (4d to 4f) transitions and the presence of surface states near the Fermi level in Ni (3p to 3d) transitions were observed, with different ion doses associated with oxygen vacancies. Interestingly, the density of states (DOS) at the Fermi level in Ni (3p to 3d) transition spectra increased systematically with the irradiation dose, and a correlation between DOS at the Fermi level and surface states was found. The highest dose sample exhibited surface states with the highest DOS at the Fermi level, indicating an upward shift of surface states with increasing irradiation dose.
SURFACES AND INTERFACES
(2023)
Article
Nanoscience & Nanotechnology
Jose P. B. Silva, Ruben Alcala, Uygar E. Avci, Nick Barrett, Laura Begon-Lours, Mattias Borg, Seungyong Byun, Sou-Chi Chang, Sang-Wook Cheong, Duk-Hyun Choe, Jean Coignus, Veeresh Deshpande, Athanasios Dimoulas, Catherine Dubourdieu, Ignasi Fina, Hiroshi Funakubo, Laurent Grenouillet, Alexei Gruverman, Jinseong Heo, Michael Hoffmann, H. Alex Hsain, Fei-Ting Huang, Cheol Seong Hwang, Jorge Iniguez, Jacob L. Jones, Ilya V. Karpov, Alfred Kersch, Taegyu Kwon, Suzanne Lancaster, Maximilian Lederer, Younghwan Lee, Patrick D. Lomenzo, Lane W. Martin, Simon Martin, Shinji Migita, Thomas Mikolajick, Beatriz Noheda, Min Hyuk Park, Karin M. Rabe, Sayeef Salahuddin, Florencio Sanchez, Konrad Seidel, Takao Shimizu, Takahisa Shiraishi, Stefan Slesazeck, Akira Toriumi, Hiroshi Uchida, Bertrand Vilquin, Xianghan Xu, Kun Hee Ye, Uwe Schroeder
Summary: Ferroelectric hafnium and zirconium oxides have shown significant progress in ultralow-power electronic systems, but technical limitations still hinder their application. This article aims to provide a comprehensive overview of the current state, challenges, and prospects for the development of these materials, with the collaboration of experts from different fields.
Article
Engineering, Electrical & Electronic
Alberto Quintana, Carlos Zarco, Nico Dix, Florencio Sanchez, Ignasi Fina, Josep Fontcuberta
Summary: Flexible FeRh films of high crystalline quality can be synthesized by using mica as a substrate, followed by a mechanical exfoliation of the mica, which display a sharp antiferromagnetic to ferromagnetic phase transition. The films exhibit two distinguishable resistance states that can be written after a field-cooling procedure, and the memory states are robust under magnetic fields of up to 10 kOe.
ACS APPLIED ELECTRONIC MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Huan Tan, Tingfeng Song, Nico Dix, Florencio Sanchez, Ignasi Fina
Summary: The piezoelectric response in doped ferroelectric HfO2 polycrystalline films has been investigated. The lack of texture in most films hinders a thorough understanding. Epitaxial films enable modification of the ferroelectric phase ratio and crystallographic orientation, providing further insight into the piezoelectric response. The magnitude of the in-plane and out-of-plane piezoelectric responses is mainly governed by the orthorhombic phase and the polar axis of the polarization along the probing direction.
JOURNAL OF MATERIALS CHEMISTRY C
(2023)
Article
Engineering, Electrical & Electronic
Xiao Long, Huan Tan, Florencio Sanchez, Ignasi Fina, Josep Fontcuberta
Summary: The recent discovery of ferroelectricity in doped HfO2 has opened possibilities for the development of memristors based on ferroelectric switching. In this study, ferroelectricity and significant electro-resistance were observed in Hf0.5Zr0.5O2 tunnel junctions grown on Si. After a soft breakdown, where the resistance decreased by five orders of magnitude, ferroelectricity and electroresistance were still observed.
ACS APPLIED ELECTRONIC MATERIALS
(2023)
Article
Physics, Applied
Tingfeng Song, Veniero Lenzi, Jose P. B. Silva, Luis Marques, Ignasi Fina, Florencio Sanchez
Summary: The influence of stress and strain on the stabilization of polar phases and ferroelectric properties is investigated in polycrystalline ferroelectric HfO2 films. Experimental and computational results reveal that stress plays a critical role in the stabilization of the orthorhombic phase and ferroelectric polarization, while lattice deformation effects are relatively small.
APPLIED PHYSICS REVIEWS
(2023)
Article
Nanoscience & Nanotechnology
Tingfeng Song, Panagiotis Koutsogiannis, Cesar Magen, Jose A. Pardo, Florencio Sanchez, Ignasi Fina
Summary: Ferroelectric hafnia is a promising material for non-volatile memory devices, and interface engineering with ZrO2 capping layer can improve its functional properties by reducing defects and interface capacitance contribution.
ADVANCED ELECTRONIC MATERIALS
(2023)
