Few-layer Tellurium, an elementary semiconductor, succeeds most of striking physical properties that black phosphorus (BP) offers and could be feasibly synthesized by simple solution-based methods. It is comprised of non-covalently bound parallel Te chains, among which covalent-like feature appears. This feature is, we believe, another demonstration of the previously found covalent-like quasi-bonding (CLQB) where wavefunction hybridization does occur. The strength of this inter-chain CLQB is comparable with that of intra-chain covalent bonding, leading to closed stability of several Te allotropes. It also introduces a tunable bandgap varying from nearly direct 0.31 eV (bulk) to indirect 1.17 eV (2L) and four (two) complex, highly anisotropic and layer-dependent hole (electron) pockets in the first Brillouin zone. It also exhibits an extraordinarily high hole mobility (∼10⁵ cm²/Vs) and strong optical absorption along the non-covalently bound direction, nearly isotropic and layer-dependent optical properties, large ideal strength over 20%, better environmental stability than BP and unusual crossover of force constants for interlayer shear and breathing modes. All these results manifest that the few-layer Te is an extraordinary-high-mobility, high optical absorption, intrinsic-anisotropy, low-cost-fabrication, tunable bandgap, better environmental stability and nearly direct bandgap semiconductor. This “one-dimension-like” few-layer Te, together with other geometrically similar layered materials, may promote the emergence of a new family of layered materials.

少层碲是一种基本半导体，继承了黑磷 (BP) 提供的大部分显着物理特性，并且可以通过简单的基于溶液的方法合成。它由非共价结合的平行Te链组成，其中出现类共价特征。我们认为，此功能是先前发现的波函数杂交确实发生的类共价准键合 (CLQB) 的另一个证明。这种链间 CLQB 的强度与链内共价键的强度相当，导致几种 Te 同素异形体的闭合稳定性。它还在第一布里渊区引入了一个可调谐带隙，从几乎直接的 0.31 eV（体）到间接的 1.17 eV (2L) 和四个（两个）复杂的、高度各向异性和层依赖的空穴（电子）袋。⁵  cm ² /Vs)和沿非共价键合方向的强光吸收，近各向同性和层依赖性光学性质，大的理想强度超过20%，比BP更好的环境稳定性以及层间剪切和呼吸力常数的不寻常交叉模式。所有这些结果表明，少层 Te 是一种非常高迁移率、高光吸收、本征各向异性、低成本制造、可调带隙、更好的环境稳定性和近直接带隙半导体。这种“类一维”少层 Te 与其他几何相似的层状材料一起，可能会促进新的层状材料家族的出现。