A5008517351- Multiferroics and related materials
- Ferroelectric and Piezoelectric Materials
- Metal and Thin Film Mechanics
- Crystallization and Solubility Studies
- Diamond and Carbon-based Materials Research
- X-ray Diffraction in Crystallography
- Magnetic and transport properties of perovskites and related materials
- Adhesion, Friction, and Surface Interactions
- Electronic and Structural Properties of Oxides
- Ferroelectric and Negative Capacitance Devices
- Advanced Memory and Neural Computing
- Magnetic properties of thin films
- Semiconductor materials and devices
- Ga2O3 and related materials
- Dielectric properties of ceramics
- Cellular and Composite Structures
- Nanowire Synthesis and Applications
- Copper Interconnects and Reliability
- 2D Materials and Applications
- Perovskite Materials and Applications
- Magnetic Properties and Applications
- Smart Materials for Construction
- Transportation Safety and Impact Analysis
- Physics of Superconductivity and Magnetism
- Semiconductor Lasers and Optical Devices
University of Warwick
2015-2023
Hefei University
2023
RIKEN Center for Emergent Matter Science
2021-2022
Shanghai Institute of Ceramics
2013-2015
Chinese Academy of Sciences
2013-2015
Hefei National Center for Physical Sciences at Nanoscale
2013
University of Science and Technology of China
2013
Nanjing University of Science and Technology
2013
Hong Kong Polytechnic University
2013
IBM (United States)
1984-1994
It is highly desirable to discover photovoltaic mechanisms that enable enhanced efficiency of solar cells. Here we report the bulk effect, which free from thermodynamic Shockley-Queisser limit but usually manifested only in noncentrosymmetric (piezoelectric or ferroelectric) materials, can be realized any semiconductor, including silicon, by mediation flexoelectric effect. We used either an atomic force microscope a micrometer-scale indentation system introduce strain gradients, thus...
Neuromorphic visual sensory and memory systems, which can perceive, process, memorize optical information, represent core technology for artificial intelligence robotics with autonomous navigation. An optoelectronic synapse an elegant integration of biometric sensing synaptic learning functions be a fundamental element the hardware-implementation such systems. Here, we report class ferroelectric field-effect memristive transistors made two-dimensional WS2 semiconductor atop PbZr0.2Ti0.8O3...
Manipulation of ferroic order parameters, namely (anti-)ferromagnetic, ferroelectric, and ferroelastic, by light at room temperature is a fascinating topic in modern solid-state physics due to potential cross-fertilization research fields that are largely decoupled. Here, full optical control, is, reversible switching, the ferroelectric/ferroelastic domains BiFeO3 thin films mediation tip-enhanced photovoltaic effect demonstrated. The enhanced short-circuit photocurrent density tip contact...
Defect-engineered perovskite oxides that exhibit ferroelectric and photovoltaic properties are promising multifunctional materials. Though introducing gap states by transition metal doping on the B-site can obtain low bandgap (i.e., 1.1-3.8 eV), electrically leaky generally lose piezoelectricity mainly due to oxygen vacancies. Therefore, development of highly piezoelectric semiconductor remains challenging. Here, inspired point-defect-mediated large in ferroelectrics especially at...
Piezoelectric materials convert mechanical stress to electrical energy and thus are widely used in harvesting wearable devices. However, the piezoelectric family, there two pairs of properties that improving one them will generally compromises other, which limits their applications. The first pair is strain voltage constant, second performance softness. Here, we report a molecular bond weakening strategy mitigate these issues organic-inorganic hybrid piezoelectrics. By introduction...
Abstract Inherent symmetry breaking at the interface has been fundamental to a myriad of physical effects and functionalities, such as efficient spin–charge interconversion, exotic magnetic structures an emergent bulk photovoltaic effect. It recently demonstrated that asymmetry can induce sizable piezoelectric in heterostructures, even those consisting centrosymmetric semiconductors, which provides flexibility develop optimize electromechanical coupling phenomena. Here, by targeted...
The bulk photovoltaic effect of ferroelectric semiconductors is increasingly being studied for potential applications in solar energy harvesting thanks to their unique charge separation mechanism and the resultant anomalous photovoltage. However, intrinsic properties regarding temperature dependence current its correlation with polarization such systems still require proper understanding. Here, by studying monodomain BiFeO3 thin films only a single variant, we demonstrate that possesses...
Abstract Domain walls, which are intrinsically two dimensional nano-objects exhibiting nontrivial electronic and magnetic behaviours, have been proven to play a crucial role in photovoltaic properties of ferroelectrics. Despite this recognition, the domain walls under illumination until now accessible only macroscopic studies their effects upon conduction current still remain elusive. The lack understanding hinders developing nanoscale devices based on ferroelectric walls. Here, we directly...
Abstract It has been recently shown that the strain gradient is able to separate light-excited electron-hole pairs in semiconductors, but how it affects photoelectric properties of photo-active materials remains an open question. Here, we demonstrate critical role mediating local strained BiFeO 3 thin films by systematically characterizing conduction with nanometre lateral resolution both dark and illuminated conditions. Due giant manifested at morphotropic phase boundaries, associated...
Abstract Flexible and self-powered deep ultraviolet (UV) photodetectors are pivotal for next-generation electronic skins to enrich human life quality. The fabrication of epitaxial β-Ga 2 O 3 thin films is challenging on flexible substrates due high-temperature growth requirements. Herein, ( $$\stackrel{-}{2}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mover><mml:mn>2</mml:mn><mml:mo>-</mml:mo></mml:mover></mml:math> 0 1) hetero-epitaxially grown ultra-thin...
The sub-band levels situated around 2.2 eV within the band gap are at electronic origin of anomalous photovoltaic effect in BiFeO3 single crystals. photovoltaic can be effectively tailored by controlling activity via thermal and electrical treatments. As a service to our authors readers, this journal provides supporting information supplied authors. Such materials peer reviewed may re-organized for online delivery, but not copy-edited or typeset. Technical support issues arising from (other...
The light control of nonvolatile nanoscale memories could represent a fundamental step toward novel optoelectronic devices with memory and logic functionalities. However, most the proposed exhibit insufficient in terms reversibility, data retention, photosensitivity, limited-photoactive area, so forth. Here, proof-of-concept work, we demonstrate use tip-enhanced bulk photovoltaic (BPV) effect to realize programmable nanoscopic writing nonphotoactive electronic by control. We show that...
Phase-separated La0.335Pr0.335Ca0.33MnO3 films were epitaxially grown on (001)- and (111)-oriented ferroelectric single-crystal substrates. Upon poling along the [001] or [111] direction, dramatic decrease in resistance, up to 99.98%, complete melting of charge-ordered phase observed, caused by poling-induced strain rather than accumulation electrostatic charge at interface. Such effects can be effectively tuned a magnetic field mediated electronic separation. In particular, our findings...
Abstract Multiferroic BiFeO 3 crystals were investigated by means of micro-Raman spectroscopy using the laser wavelengths 442 nm (resonant conditions) and 633 (non-resonant conditions). The azimuthal angle dependence intensity Raman modes allowed their symmetry assignment. experimental data are consistent with a simulation based on tensor formalism. Mixed symmetries taken into account, considering orientation crystal optic axis along pseudo-cubic <111> direction. strong anisotropic...
We report exchange bias effect in Fe3O4 films epitaxially grown on SrTiO3 substrates. This is related to the formation of Ti3+-vacancy complexes at surface ultrahigh vacuum that turn triggers growth a thin antiferromagnetic (AFM) FeO layer (∼5 nm) interface. The picture interacting with native ferrimagnetic matrix reasonably accounts for this anomalous magnetic behavior. With increasing film thickness from 17 43 nm, and magnetization anomaly associated AFM phase transition are progressively...
We report in situ manipulation of the in-plane strain εxx(BFMO) and coercive field EC(BFMO) BiFe0.95Mn0.05O3 (BFMO) films epitaxially grown on La0.7Sr0.3MnO3 film buffered 0.71Pb(Mg1/3Nb2/3)O3-0.29PbTiO3 (PMN-PT) substrates. PMN-PT poling-induced is effectively transferred to enhances EC(BFMO), with a gauge factor (ΔEC(BFMO)/EC(BFMO))/(δεxx) ∼−25 −326 for BFMO(001) BFMO(111) films, respectively. Based dependence we established quantitative relationship between εxx(BFMO). Using ferroelastic...
The giant tunnelling electroresistance (TER) and memristive behaviours of ferroelectric tunnel junctions make them promising candidates for future information storage technology. Using conducting ferromagnetic layers as electrodes results in multiferroic (MFTJs) which show spin dependent transport. magnetoresistance (TMR) such structures can be reversibly controlled by electric pulsing owing to polarisation-dependent polarisation at the ferroelectric/ferromagnetic interface. Here, we...
Gallium oxide (β-Ga2O3) is emerging as a promising wide-bandgap semiconductor for optoelectronic and high-power electronic devices. In this study, deep-level defects were investigated in pulsed-laser-deposited epitaxial films of β-Ga2O3. A deep ultraviolet photodetector (DUV) fabricated on β-Ga2O3 film showed slow decay time 1.58 s after switching off 250 nm wavelength illumination. Generally, possesses various intentional unintentional trap levels. Herein, these traps using the fractional...
An atomic force microscope-based nanoscratch testing technique has been applied to evaluate scratch resistance of 100 Å thick protective overcoats on hard magnetic disks. Among the prepared by dc magnetron sputtering, an amorphous nitrogenated carbon (a-C:N) film showed best performance in tests, followed hydrogenated (a-C:H) and undoped (a-C) film. Substrate temperature overcoat sputtering process was found be important factor affecting film’s resistance. Overcoats sputtered at lower...