A5030957290- Phase-change materials and chalcogenides
- Chalcogenide Semiconductor Thin Films
- 2D Materials and Applications
- Graphene research and applications
- Advanced Memory and Neural Computing
- Transition Metal Oxide Nanomaterials
- MXene and MAX Phase Materials
- ZnO doping and properties
- Nonlinear Optical Materials Studies
- Semiconductor materials and devices
- Quantum Dots Synthesis And Properties
- Perovskite Materials and Applications
- Electronic and Structural Properties of Oxides
- Advanced Photocatalysis Techniques
- Laser Material Processing Techniques
- Thin-Film Transistor Technologies
- Organic Electronics and Photovoltaics
- Diamond and Carbon-based Materials Research
- Advancements in Battery Materials
- Boron and Carbon Nanomaterials Research
- Photonic Crystals and Applications
- Solid-state spectroscopy and crystallography
- Glass properties and applications
- Photonic and Optical Devices
- Ga2O3 and related materials
State Key Laboratory on Integrated Optoelectronics
2016-2025
Jilin University
2016-2025
Capital Medical University
2013-2025
Beijing Anding Hospital
2013-2025
Guizhou University
2023-2025
Integrated Optoelectronics (Norway)
2025
Jilin Medical University
2014-2025
Harbin University of Science and Technology
2025
Hefei University of Technology
2023-2024
Jiujiang University
2024
A systematic study of 32 honeycomb monolayer II-VI semiconductors is carried out by first-principles methods. While none the two-dimensional (2D) structures can be energetically stable, it appears that BeO, MgO, CaO, ZnO, CdO, CaS, SrS, SrSe, BaTe, and HgTe monolayers have a good dynamic stability. The stability five oxides consistent with work published Zhuang et al. [Appl. Phys. Lett. 103, 212102 (2013)]. rest compounds in form are dynamically unstable, revealed phonon calculations. In...
To date, slow Set operation speed and high Reset power remain to be important limitations for substituting dynamic random access memory by phase change memory. Here, we demonstrate cell based on Ti0.4Sb2Te3 alloy, showing one order of magnitude faster as low one-fifth power, compared with Ge2Sb2Te5-based at the same size. The enhancements may rooted in common presence titanium-centred octahedral motifs both amorphous crystalline phases. essentially unchanged local structures around titanium...
Abstract Metasurfaces have been extensively studied for generating electromagnetic waves carrying orbital angular momentum (OAM). In particular, programmable metasurfaces enable real‐time switching between multiple OAM modes in a digital manner. However, the current are mostly based on reflective mode, which suffer from low efficiency as well serious feed blockage. this paper, transmissive metasurface is presented highly efficient generation of multimode convergent beams. The proposed...
Abstract In emerging optoelectronic applications, such as water photolysis, exciton fission and novel photovoltaics involving low-dimensional nanomaterials, hot-carrier relaxation extraction mechanisms play an indispensable intriguing role in their photo-electron conversion processes. Two-dimensional transition metal dichalcogenides have attracted much attention above fields recently; however, insight into the mechanism of hot electron-hole pairs band nesting region denoted C-excitons,...
Abstract Ferroelectric memory is a promising candidate for next‐generation nonvolatile owing to its outstanding performance such as low power consumption, fast speed, and high endurance. However, the ferroelectricity of conventional ferroelectric materials will be eliminated by depolarization field when size drops nanometer scale. As result, miniaturization devices was hindered, which makes unable keep up with development integrated‐circuit (IC) miniaturization. Recently, two‐dimensional...
The Si-based integrated circuits industry has been developing for more than half a century, by focusing on the scaling-down of transistor. However, miniaturization transistors will soon reach its physical limits, thereby requiring novel material and device technologies. Resistive memory is promising candidate in-memory computing energy-efficient synaptic devices that can satisfy computational demands future applications. poor cycle-to-cycle device-to-device uniformities hinder mass...
Abstract To meet the requirement of big data era and neuromorphic computations, nonvolatile memory with fast speed, high density, low power consumption is urgently needed. As an emerging technology, phase‐change a promising candidate to solve this problem. However, drawback hinders their applications. Most recently, new material [(GeTe) x /(Sb 2 Te 3 ) y ] n superlattice attracts intensive attentions owing its ultralow comparing conventional devices. Many studies on have been reported. there...
Reported here is femtosecond laser mediated bandgap tailoring of graphene oxides (GOs) for direct fabrication graphene-based microdevices. When pulses were used to reduce and pattern GO, oxygen contents in the reduced region could be modulated by varying power. In this way, GO was precisely from 2.4 0.9 eV tuning power 0 23 mW. Through first-principle study, essence proved reduction induced oxygen-content modulation. As representative illustrations, bottom-gate FETs fabricated situ using as...
Phase-change materials are highly promising for next-generation nonvolatile data storage technology. The pronounced effects of C doping on structural and electrical phase-change behaviors Ge2Sb2Te5 material investigated at the atomic level by combining experiments ab initio molecular dynamics. dopants found to fundamentally affect amorphous structure altering local environments Ge–Te tetrahedral units with stable C–C chains. incorporated increases stability due enhanced covalent nature...
First-principles molecular dynamics simulation reveals the effects of electronic excitation in amorphization Ge-Sb-Te. The makes phase change an element-selective process, lowers critical temperature considerably, for example, to below 700 K at a 9% excitation, and reduces atomic diffusion coefficient with respect that melt by least 1 order magnitude. Noticeably, resulting structure has fewer wrong bonds significantly increased phase-change reversibility. Our results point new direction...
Using hybrid functional calculation, we identify the key intrinsic defects in Cu${}_{2}$ZnSnS${}_{4}$ (CZTS), an important earth-abundant solar-cell material. The Sn-on-Zn antisite and defect complex having three Cu atoms occupying a Sn vacancy are found to be main deep electron traps. This result explains optimal growth condition for CZTS, which is poor Zn rich, as several recent experiments. We show that, under that minimizes traps, could contribute majority of hole carriers, while...
The strong interaction between graphene oxides (GO) and water molecules has trigged enormous research interest in developing GO-based separation films, sensors, actuators. However, sophisticated control over the ultrafast transmission among GO sheets consequent deformation of entire film is still challenging. Inspired from natural "quantum-tunneling-fluidics-effect," here quantum-confined-superfluidics-enabled moisture actuation paper by introducing periodic gratings unilaterally reported....
We present a design concept of thin-film organic solar cells using photonic crystal as the electrode. Through excitation optical Tamm states (OTSs), proposed based (PC-OSCs) exhibit broad-band absorption enhancement owing to abnormal refractive index variation active layer. The overall absorptivity can be increased by ∼35% compared with that optimized conventional planar OSC. Remarkably, our easily manufactured PC-OSC exhibits almost same corrugated excellent performance comes from...
We present a simple and efficient approach to evaluate the formation energy and, in particular, ionization (IE) of charged defects two-dimensional (2D) systems using supercell approximation. So far, first-principles results for such can scatter widely due divergence Coulomb with vacuum dimension, denoted here as L_{z}. Numerous attempts have been made past fix problem under various approximations. Here, we show that be resolved without any assumption, converged IE obtained by an...
Two-dimensional (2D) honeycomb systems made of elements with d electrons are rare. Here, we report the fabrication a transition metal (TM) 2D layer, namely, hafnium crystalline layers on Ir(111). Experimental characterization reveals that Hf layer has its own lattice, morphologically identical to graphene. First-principles calculations provide evidence for directional bonding between adjacent atoms, analogous carbon atoms in Calculations further suggest freestanding could be ferromagnetic...
It remains a remarkable challenge to develop practical techniques for controllable and nondestructive doping in two-dimensional (2D) materials their use electronics optoelectronics. Here, we propose modulation strategy, wherein the perfect n-/p-type channel layer is achieved by accepting/donating electrons from/to defects inside an adjacent encapsulation layer. We demonstrate this strategy heterostructures of BN/graphene, BN/MoS2, where previously believed useless deep defects, such as...
Abstract Phase change memory (PCM) is an emerging non‐volatile data storage technology concerned by the semiconductor industry. To improve performances, previous efforts have mainly focused on partially replacing or doping elements in flagship Ge‐Sb‐Te (GST) alloy based experimental “trial‐and‐error” methods. Here, current largest scale PCM materials searching reported, starting with 124 515 candidate materials, using a rational high‐throughput screening strategy consisting of criteria...
Abstract Understanding Mott insulators and charge density waves (CDW) is critical for both fundamental physics future device applications. However, the relationship between these two phenomena remains unclear, particularly in systems close to two-dimensional (2D) limit. In this study, we utilize scanning tunneling microscopy/spectroscopy investigate monolayer 1T-NbSe 2 elucidate energy of upper Hubbard band (UHB), reveal that spin-polarized UHB spatially distributed away from dz orbital at...
Abstract Phase‐change random‐access memory (PCRAM) devices suffer from pronounced resistance drift originating considerable structural relaxation of phase‐change materials (PCMs), which hinders current developments high‐capacity and high‐parallelism computing that both need reliable multibit programming. This work realizes compositional simplification geometrical miniaturization traditional GeSbTe‐like PCMs are feasible routes to suppress relaxation. While date, the aging mechanisms simplest...