自从量子自旋霍尔效应首次在(Hg,Cd)Te 量子阱中被发现以来,人们认为类似于HgTe这种具有“反带”结构的性质,是拓扑绝缘体形成的前提条件.传统的半导体材料中,导带的最低点都是由阳离子的s轨道电子所占据,即Γ6,而价带的最高点则是由阴离子p轨道电子所占据.由于重原子存在较强的自旋轨道相互作用,原本的一条带被劈裂成两条带,即Γ8、Γ7.而在具有“反带”结构的材料中,Γ6与Γ8的能量值恰好相反,汞
A new family of two-dimensional(2D)topological insulators(TIs),g-TlA(A = N,P,As,and Sb)monolayers,constructed by Tl and group V elements is predicted by first-principles calculations and molecule dyna
Approaching the glass transition of a metallic glass,the dramatic change of the dynamic properties still remains elusive from the microscopic aspect.In CuZr metallic glasses icosahedral clusters have
In this talk,we discuss several new effects in predicting and optimizing the thermoelectric performance of some example systems.We first show that band convergence in the Mg2Si1-xSnx solid solutions a
We study experimentally the jamming phenomenon of granular flow of bidisperse disks in a 2D hopper driven by gravity.When particles flow through a bottleneck,there is a probability that the system wil
天然酶是生物体内细胞合成的一种非常高效的催化剂，具有效率高、专一性强、作用条件温和等特点。除了行驶其自然功能外，已经被广泛地运用到生物、化学工业等各个领域。但是酶固有的缺点(如：价格昂贵、易失活、储存稳定性差等)限制了其进一步应用。
The engineering of defects in crystalline matter has been extensively exploited to modify the mechanical and electrical properties of many materials.Recent experiments on manipulating extended defects
In this study,we investigate the granular materials in a 2D Couette cell under shear using photo-elastic disks.For initial packing fractions \phi smaller than \phi_c=82%,an initially stress-free state
Granular avalanches are ubiquitous in nature.There a key question is whether it is possible to identify a priorimeso-scale structure to predict the possible location of the instability of the system.I
Graphene functionalization has been an important research topic in practical applications of electronic devices.Adsorption of molecules on graphene is an effective route to achieve graphene novel func