A5100390592- 2D Materials and Applications
- Graphene research and applications
- MXene and MAX Phase Materials
- Iron-based superconductors research
- Crystallization and Solubility Studies
- Perovskite Materials and Applications
- X-ray Diffraction in Crystallography
- Rare-earth and actinide compounds
- Carbon Nanotubes in Composites
- Chalcogenide Semiconductor Thin Films
- Electronic and Structural Properties of Oxides
- Diamond and Carbon-based Materials Research
- Corporate Taxation and Avoidance
- Magnetic and transport properties of perovskites and related materials
- ZnO doping and properties
- Supercapacitor Materials and Fabrication
- Advanced Memory and Neural Computing
- Nanowire Synthesis and Applications
- Advanced Photocatalysis Techniques
- Nonlinear Optical Materials Studies
- Advancements in Semiconductor Devices and Circuit Design
- Advanced Sensor and Energy Harvesting Materials
- Intellectual Capital and Performance Analysis
- Fiber-reinforced polymer composites
- Transition Metal Oxide Nanomaterials
Shanghai Jiao Tong University
2022-2025
Pennsylvania State University
2015-2024
Chongqing University
2024
Fudan University
1995-2023
Shaanxi Xueqian Normal University
2023
Lawrence Berkeley National Laboratory
2020-2023
University of Rochester
2022-2023
Changchun University of Science and Technology
2022-2023
University of California, Berkeley
2021
Advanced Light Source
2020
Since their modern debut in 2004, 2-dimensional (2D) materials continue to exhibit scientific and industrial promise, providing a broad platform for investigation, development of nano- atomic-scale devices. A significant focus the last decade's research this field has been 2D semiconductors, whose electronic properties can be tuned through manipulation dimensionality, substrate engineering, strain, doping (Mak et al 2010 Phys. Rev. Lett. 105 136805; Zhang 2017 Sci. Rep. 7 16938; Conley 2013...
A multistep diffusion-mediated process was developed to control the nucleation density, size, and lateral growth rate of WSe2 domains on c-plane sapphire for epitaxial large area monolayer films by gas source chemical vapor deposition (CVD). The consists an initial step followed annealing period in H2Se promote surface diffusion tungsten-containing species form oriented islands with uniform size controlled density. conditions were then adjusted suppress further laterally grow a fully...
Atomically thin transition metal dichalcogenides (TMDs) are of interest for next-generation electronics and optoelectronics. Here, we demonstrate device-ready synthetic tungsten diselenide (WSe2) via metal-organic chemical vapor deposition provide key insights into the phenomena that control properties large-area, epitaxial TMDs. When epitaxy is achieved, sapphire surface reconstructs, leading to strong 2D/3D (i.e., TMD/substrate) interactions impact carrier transport. Furthermore, substrate...
A defect-controlled approach for the nucleation and epitaxial growth of WSe2 on hBN is demonstrated. The domains exhibit a preferred orientation over 95%, leading to reduced density inversion domain boundaries (IDBs) upon coalescence. First-principles calculations experimental studies as function conditions substrate pretreatment confirm that are controlled by surface defect rather than thermodynamic factors. Detailed transmission electron microscopy analysis provides support role...
In conventional Bardeen-Cooper-Schrieffer (BCS) superconductors, superconductivity occurs when electrons form coherent Cooper pairs below the superconducting transition temperature Tc. Although kinetic energy of paired increases in state relative to normal state, reduction ion lattice is sufficient give condensation energy. For iron pnictide superconductors derived from electron or hole doping their antiferromagnetic (AF) parent compounds, microscopic origin for supercnductivity unclear....
Transition metal dichalcogenide (TMD) monolayers and heterostructures have emerged as a compelling class of materials with transformative new science that may be harnessed for novel device technologies. These are commonly fabricated by exfoliation flakes from bulk crystals, but wafer-scale epitaxy single crystal films is required to advance the field. This article reviews fundamental aspects epitaxial growth van der Waals bonded crystals specific TMD films. The structural electronic...
Abstract Spin‐dependent contrasting phenomena at K and ′ valleys in monolayer semiconductors have led to addressable valley degree of freedom, which is the cornerstone for emerging valleytronic applications information storage processing. Tunable active modulation dynamics a WSe 2 demonstrated room temperature through controllable chiral Purcell effects plasmonic metamaterials. The strong spin‐dependent on spontaneous decay excitons leads tunable handedness spectral shift valley‐polarized...
The interest in two-dimensional and layered materials continues to expand, driven by the compelling properties of individual atomic layers that can be stacked and/or twisted into synthetic heterostructures. plethora electronic as well emergence many different quasiparticles, including plasmons, polaritons, trions excitons with large, tunable binding energies all controlled modulated through electrical means has given rise device applications. In addition, these exhibit both room-temperature...
The effective use of the van der Waals 2D materials relies on their successful transfer from growth substrate onto other target substrates in form large films or flakes. In particular, it is important to such atomically thin samples various with minimal sample damage and exposure etchants chemicals realize applications. Here we develop a universal method that not only free reactive etchants, but also can maintain film morphology intact no tears cracks. We show variety different crystals...
The highest quality hexagonal boron nitride (hBN) crystals are grown from molten solutions. For hBN crystal growth at atmospheric pressure, typically the solvent is a combination of two metals, one with high solubility and other to promote nitrogen solubility. In this study, we demonstrate that high-quality can be pressure using pure iron as flux. ability produce excellent-quality unexpected, given its low for nitrogen. properties produced flux matched best values ever reported hBN: narrow...
We report the emergence of a polar metal phase in layered van der Waals compound FePSe$_3$. This Mott insulator with antiferromagnetic order offers unique opportunity to fully tune an into state pressure, without doping-induced disorder or impurities. Our synchrotron and neutron diffraction data unambiguously show structural transition loss inversion symmetry. also observed suppression magnetic ordering insulator-to-metal correspondent this transformation. The symmetry combined...
Layered β′-In2Se3 has garnered significant attention due to its intriguing multiferroic properties. Until now, most studies have focused on a material-level understanding, with limited exploration of device-level This work systematically investigates the in-plane resistive switching behavior β′-In2Se3. Besides resulting from ferroelectric polarization reversal, critical role defect migration is unveiled in determining overall electrical characteristics devices. Specifically, we elucidate...
Abstract NaNiO$_2$ is a Ni$^{3+}$-containing layered material consisting of alternating triangular networks Ni and Na cations, separated by octahedrally-coordinated O anions. At ambient pressure, it features collinear Jahn--Teller distortion below $T^\mathrm{JT}_\mathrm{onset}\approx480$\,K, which disappears in broad first-order transition on heating to $T^\mathrm{JT}_\mathrm{end}\approx500$\,K, corresponding the increase symmetry from monoclinic rhombohedral. It was previously studied...
A microscopic model Hamiltonian for the ferroelectric field effect is introduced study of oxide heterostructures with components. The long-range Coulomb interaction incorporated as an electrostatic potential, solved self-consistently together charge distribution. generic double-exchange system used conducting channel, epitaxially attached to gate. observed screening effect, namely accumulation/depletion near interface, shown drive interfacial phase transitions that give rise robust...
We introduce and study an extended "t-U-J" two-orbital model for the pnictides that includes Heisenberg terms deduced from strong coupling expansion. Including these J explicitly allows us to enhance strength of (π,0)-(0,π) spin order which favors presence tightly bound pairing states even in small clusters are here exactly diagonalized. The A(1g) B(2g) symmetries found compete realistic spin-ordered metallic regime. dynamical susceptibility additionally unveils low-lying B(1g) states,...
There is significant interest in the growth of single crystal monolayer and few-layer films transition metal dichalcogenides (TMD) other 2D materials for scientific exploration potential applications optics, electronics, sensing, catalysis others. The characterization these crucial determining properties hence applications. ultra-thin nature layers presents a challenge to use x-ray diffraction (XRD) analysis with conventional Bragg-Brentano geometry analyzing crystallinity epitaxial...
Atomic defects with a four microsecond-long photoluminescence lifetime are created in single-layer WSe<sub>2</sub> by focused ion beam irradiation.
Hexagonal boron nitride (hBN) is attracting much attention due to its tremendous applications including nanophotonic and electronic devices, substrates for two-dimensional (2D) materials, heat management etc. To achieve the best device performance, large area hBN single crystals are required. Herein, large-area (>500 μm each), high-quality (defect density < 0.52/μm2) bulk grown from molten metal solutions with a temperature gradient. The narrow Raman line widths of intralayer E2g mode peak...
Superhydrophobic surfaces hold tremendous potential in a wide range of applications owing to their multifaced functionalities. However, the mechanochemical susceptibility such materials hinders widespread usage practical applications. Here, we present simple, solvent-free, and environmentally friendly approach fabricate flexible robust superhydrophobic composite films with durable self-cleaning functionality. The obtained film features unexpected but surprising hierarchical micro/nanoscopic...
The highly anisotropic resistivities in strained manganites are theoretically studied using the two-orbital double-exchange model. At nanoscale, and Jahn-Teller distortions found to be responsible for robust observed here via Monte Carlo simulations. An unbalance population of orbitals caused by strain is these effects. In contrast, superexchange irrelevant explain our results. Our model study suggests that could present a wide range manganites, even without (sub)micrometer-scale phase...