A5100435839- Topological Materials and Phenomena
- Graphene research and applications
- 2D Materials and Applications
- Physics of Superconductivity and Magnetism
- Quantum many-body systems
- Quantum and electron transport phenomena
- MXene and MAX Phase Materials
- Cold Atom Physics and Bose-Einstein Condensates
- Advanced Condensed Matter Physics
- Superconductivity in MgB2 and Alloys
- Machine Learning in Materials Science
- Advanced Chemical Physics Studies
- Boron and Carbon Nanomaterials Research
- Perovskite Materials and Applications
- Advanced Thermoelectric Materials and Devices
- Semiconductor materials and interfaces
- Quantum, superfluid, helium dynamics
- Theoretical and Computational Physics
- Mechanical and Optical Resonators
- Metal and Thin Film Mechanics
- Thermal properties of materials
- Semiconductor materials and devices
- Microstructure and mechanical properties
- Quantum Dots Synthesis And Properties
- Diamond and Carbon-based Materials Research
Inner Mongolia University
2022-2025
University of Science and Technology of China
2011-2025
Institute of Electrical Engineering
2009-2025
Chinese Academy of Sciences
2016-2025
Institute of Microelectronics
2025
University of Chinese Academy of Sciences
2016-2024
Institute of Physics
2013-2024
Northeast Forestry University
2024
Songshan Lake Materials Laboratory
2018-2024
Institute of Computing Technology
2024
Identifying two-dimensional layered materials in the monolayer limit has led to discoveries of numerous new phenomena and unusual properties. We introduced elemental silicon during chemical vapor deposition growth nonlayered molybdenum nitride passivate its surface, which enabled centimeter-scale films MoSi2N4 This was built up by septuple atomic layers N-Si-N-Mo-N-Si-N, can be viewed as a MoN2 layer sandwiched between two Si-N bilayers. material exhibited semiconducting behavior (bandgap...
Unsupervised learning is a discipline of machine which aims at discovering patterns in big data sets or classifying the into several categories without being trained explicitly. We show that unsupervised techniques can be readily used to identify phases and transitions many body systems. Starting with raw spin configurations prototypical Ising model, we use principal component analysis extract relevant low dimensional representations original clustering distinct feature space. This approach...
Motivated by the fact that septuple-atomic-layer MnBi$_2$Te$_4$ can be structurally viewed as combination of double-atomic-layer MnTe intercalating into quintuple-atomic-layer Bi$_2$Te$_3$, we present a general approach constructing twelve $\alpha_i$- and $\beta_i$-$MA_2Z_4$ monolayer family (\emph{i} = 1 to 6) MoS$_2$-type $MZ$$_2$ InSe-type A$_2$Z$_2$ monolayer. Besides reproducing experimentally synthesized $\alpha_1$-MoSi$_2$N$_4$, $\alpha_1$-WSi$_2$N$_4$ $\beta_5$-MnBi$_2$Te$_4$...
The discovery of topological quantum states marks a new chapter in both condensed matter physics and materials sciences. By analogy to spin electronic system, concepts have been extended into phonons, boosting the birth phononics (TPs). Here, we present high-throughput screening data-driven approach compute evaluate TPs among over 10,000 materials. We clarified 5014 TP classified them single Weyl, high degenerate nodal-line (ring) TPs. Among them, three representative cases discussed detail....
We study the disorder effect on transport properties in HgTe/CdTe semiconductor quantum wells. confirm that at a moderate strength, initially unquantized two-terminal conductance becomes quantized and system makes transition to topological Anderson insulator (TAI). Conductances calculated for stripe cylinder samples reveal feature of TAI supports idea helical edge states may cause anomalous plateaus. The influence is studied by calculating distributions local currents. Based above-mentioned...
A topological charge pump [1] transfers in a quantized fashion. The quantization is stable against the detailed form of pumping protocols and external noises shares same origin as quantum Hall effect. We propose an experiment setup to realize cold atoms one-dimensional optical lattice. pumped confirmed by first-principle simulations dynamics uniform trapped systems. Quantum effects are shown be crucial for protection quantization. Finite-temperature non-adiabatic effect on experimental...
Ammonium polyphosphate (APP), a widely used intumescent flame retardant, has been microencapsulated by cellulose acetate butyrate with the aim of enhancing water resistance APP and compatibility between ethylene-vinyl copolymer (EVA) matrix APP. The structure ammonium (MCAPP) was characterized Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron (XPS), scanning electron microscopy (SEM), contact angle (WCA). retadancy thermal stability were investigated limiting oxygen index...
We present a variational renormalization group (RG) approach based on reversible generative model with hierarchical architecture. The performs change-of-variables transformations from the physical space to latent reduced mutual information. Conversely, neural network directly maps independent Gaussian noises configurations following inverse RG flow. has an exact and tractable likelihood, which allows unbiased training direct access renormalized energy function of variables. To train model,...
By means of first-principles calculations and a modeling analysis, we have predicted that traditional two-dimensional graphene hosts four types topological phononic Dirac points (DPs) nodal ring (PNR) in its phonon spectrum. In the spectrum graphene, there exist DPs, DP1, DP2, DP3, DP4, with both DP1 DP2 located at Brillouin zone (BZ) corners $K$ ${K}^{\ensuremath{'}}$, DP3 along $\mathrm{\ensuremath{\Gamma}}\text{\ensuremath{-}}K$ line, DP4...
Based on first-principles calculations, we predict that the superconducting MgB$_2$ with a AlB$_2$-type centrosymmetric lattice host so-called phononic topological Weyl nodal lines (PTWNLs) its bulk phonon spectrum. These PTWNLs can be viewed as countless points (WPs) closely aligned along straight in $-$H-K-H direction within three-dimensional Brillouin zone (BZ). Their non-trivial natures are confirmed by calculated Berry curvature distributions planes perpendicular to these lines. highly...
Phase engineering of nanomaterials (PEN) has demonstrated great potential in the fields catalysis, electronics, energy storage and conversion, condensed matter physics. Recently, transition metal dichalcogenides (TMDs) with unconventional metastable phases (e.g., 1T 1T') have attracted increasing research interest due to their unique appealing physicochemical properties. However, there is still a lack simple, universal, controlled method for preparation large-scale high-purity...
Exploration of multiphase coexistence has always been an important topic in condensed matter physics, which can produce rich physics to meet the needs modern science and technology. In this work, by means first-principles calculations, we successfully predicted ferroelectricity charge density wave (CDW) material 1T−TiX2 (X = S, Se, Te) bilayers stacking two van der Waals (vdW) monolayers. Because CDW transition occurring at low temperatures is accompanied a metal-insulator (MIT),...
We introduce in detail our newly developed \textit{ab initio} LDA+Gutzwiller method, which the Gutzwiller variational approach is naturally incorporated with density functional theory (DFT) through "Gutzwiller (GDFT)" (which a generalization of original Kohn-Sham formalism). This method can be used for ground state determination electron systems ranging from weakly correlated metal to strongly insulators long-range ordering. will show that its quality as high by dynamic mean field (DMFT),...
The metal-free synthesis of graphene on single-crystal silicon substrates, the most common commercial semiconductor, is paramount significance for many technological applications. In this work, we report growth directly an upside-down placed, substrate using metal-free, ambient-pressure chemical vapor deposition. By controlling temperature, in-plane propagation, edge-propagation, and core-propagation, process can be identified. This produces atomically flat monolayer or bilayer domains,...
We present a guiding principle for designing fermionic Hamiltonians and quantum Monte Carlo (QMC) methods that are free from the infamous sign problem by exploiting Lie groups algebras appear naturally in weight of QMC simulations. Specifically, rigorous mathematical constraints on determinants involving matrices lie split orthogonal group provide guideline sign-free simulations models bipartite lattices. This not only unifies recent solutions based continuous-time Majorana representation,...
We propose an experimental technique for classifying the topology of band structures realized in optical lattices, based on a generalization topological charge pumping quantum Hall systems to cold atoms lattices. Time-of-flight measurement along one spatial direction combined with situ detection transverse provides direct measure system's Chern number, as we illustrate by calculations Hofstadter lattice. Based analogy Wannier function techniques theory, method is very general and also allows...
The class of topological semimetals comprises a large pool compounds. Together they provide wide platform to realize exotic quasiparticles for example Dirac, nodal line Dirac and Weyl fermions. In this letter, we report the Berry phase, Fermi surface topology anisotropic magnetoresistance HfSiS which has recently been predicted be semimetal. This compound contains carrier density, higher than most known semimetals. Massive amplitudes de Haas-van Alphen Shubnikov-de Haas oscillations up 20 K...
The nonlinear optical performance of layered MoS<sub>2</sub> nanofilms was successfully modulated by defect engineering <italic>via</italic> a polyelectrolyte-assisted annealing process.
Spinless fermions on a honeycomb lattice provide minimal realization of Dirac fermions. Repulsive interactions between nearest neighbors drive quantum phase transition from semimetal to charge-density-wave state through fermionic critical point, where the coupling Ising order parameter at low energy drastically affects behavior. Encouraged by recently discovery absence fermion sign problem in this model, we study point using continuous time Monte Carlo method with worm sampling technique. We...