Abstract We investigate semi-analytically the coherent electronic transport properties of a bent, twisted, compacted or stretched simple cubic nanocrystal within the nearest neighbor tight-binding approach and Green’s function technique. We take the bent, twisted, compacted and stretched part of the nanocrystal as a center wire and the other ideal parts as two semi-infinite similar left and right leads. Also, the cross-section of the wire is assumed to have square shape consisting of a finite number of atoms. We use a unitary transformation to separate the conductance modes in the ideal parts in order to calculate fully analytically center wire self-energies due to the existence of ideal leads. Then, we compute numerically the transport properties of the system by using the transformed Green’s function of the center wire which includes these self-energies. The results show that for bent and twisted configuration, some localized states form in perturbed part. The compacting has more influence on the electronic transport with respect to stretching. Also, the value of conductance at zero (Fermi) energy depends on the deformation strength in compacted and twisted nanocrystals.

中文翻译：

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变形简单立方纳米晶电子输运特性的半解析研究

摘要 我们在最近邻紧束缚方法和格林函数技术中半分析地研究了弯曲、扭曲、压缩或拉伸的简单立方纳米晶体的相干电子输运特性。我们将纳米晶体的弯曲、扭曲、压实和拉伸部分作为中心线，其他理想部分作为两个半无限相似的左右引线。此外，假设导线的横截面具有由有限数量的原子组成的方形。我们使用单一变换来分离理想部件中的电导模式，以便完全解析地计算由于存在理想引线而导致的中心线自能。然后，我们通过使用包含这些自能的中心线的转换格林函数来数值计算系统的传输特性。结果表明，对于弯曲和扭曲配置，在扰动部分会形成一些局部状态。就拉伸而言，压实对电子传输的影响更大。此外，零（费米）能量下的电导值取决于压实和扭曲纳米晶体的变形强度。