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Yunhu Zhu

Publications and source records attributed to Yunhu Zhu.

6 recordsLinked to original sources

Quantum Divergence and Topological Edge Diagnostics via Levitov Full Counting Statistics

We propose a differential full counting statistics protocol for mesoscopic transport. Additionally, we compare terminal Fano factors and noise cumulants between gate configurations at matched k1, instead of inferring a bulk divergence sensor from a single absolute F. it is illustrated analytically for a two channel factorization via a zero temperature geometry scan. Secondary benchmarks show that a two dimensional lattice non equilibrium Greens function calculation yields sub Poissonian Fano factors, whereas Kumars low temperature quantum point contact calibration validates the numerical implementation.

cond-mat.mes-hall

Non-Hermitian Tight-Binding Bands in Graphene: Optical Conductivity, Strain Effects, and Bernal Bilayer Extension

Within the tight binding framework of graphenes π electron nearest neighbors, the Tan Bo model parametrizes transition energies t(dr) based on bond lengths and angles via the Mobius transformation combined with exponential decay. Comparisons between isotropic , geometrically anisotropic , and Slater Koster scales reveal that B = 0 is equivalent to the SK scheme, with L(B) reaching its optimum at Bopt = 0. The Hermitian assembly maintains the Dirac cone at the K point.The Tan Bo geometry dependent transition model and non Hermitian TB assembly scheme developed in this study provide a reproducible single particle benchmark and parameterization reference for future non Hermitian chemical calculations incorporating electron correlation effects in graphene systems.

cond-mat.mtrl-sci

Electrostatic Screening Modulation of Graphene's Electronic Structure and the Helical Wavefunction Dominated Topological Properties

This study examines electrostatic screening effects in graphene using tight binding calculations based on the Binding energy and Bond Charge model and a modified version of it. The results indicate that the modified BBC potential decays in an exponential manner with distance, which suppresses electron electron interactions. The hopping integrals exhibit a pronounced decrease over distance and shift with parameter variation. A band gap opens once the parameter exceeds a certain threshold. The density of states shows a prominent peak near the Fermi level, whereas the low-energy region remains largely unchanged. The low energy helical wave functions in graphene display topological characteristics, including pseudospin momentum locking and a π Berry phase, resulting in distinctive transport properties. By avoiding the Coulomb singularity, the model offers valuable insights for the engineering of screening in two-dimensional systems and the design of topological devices.

cond-mat.mes-hall

Study the quantum resolution sizes and atomic bonding states of two-dimensional tin monoxide

Understanding the interatomic bonding and electronic properties of two-dimensional (2D) materials is crucial for preparing high-performance 2D semiconductor materials. We have calculated the band structure, electronic properties, and bonding characteristics of SnO in 2D materials by using density functional theory (DFT) and combining bond energy and bond charge models. Atomic bonding analysis enables us to deeply and meticulously analyze the interatomic bonding and charge transfer in the layered structure of SnO. This study greatly enhances our understanding of the local bonding state on the surface of 2D structural materials. In addition, we use the renormalization method to operate energy to determine the wave function at different quantum resolutions. This is of great significance for describing the size and phase transition of nanomaterials.

cond-mat.mtrl-sci

Atomic bonding and electrical characteristics of two-dimensional graphene/boron nitride van der Waals heterostuctures with manufactured defects via binding energy and bond-charge model

We used the binding energy-bond-charge model to study the atomic bonding and electrical properties of the two-dimensional graphene/BN van der Waals heterostructure. We manipulated its atomic bonding and electrical properties by manufacturing defects. We discovered that this process yielded a band structure with a flat band, i.e., a horizontal band structure without dispersion at the Fermi level. Thus, our research is significant because it is the first report on this flat band of defect graphene/BN van der Waals heterostructures.

cond-mat.mtrl-sci

Bond relaxation and electronic properties of T type WTe$_2$/MoS$_2$ heterostructure using BOLS BB and BC model

We combined the bond order length strength and bond charge models and the topological concept to obtain the nonbonding, bonding, and antibonding states of the T type WTe$_2$/MoS$_2$ heterostructure.The energy band projection method and electronic information entropy are remarkable approaches for analyzing the electronic properties of various structures based on DFT calculations. This study provides a new way to describe the electronic properties of T type heterostructures and calculate the electron and bonding state probabilities.

cond-mat.mtrl-sci