Effect of atomic-scale defects and dopants on phosphorene electronic structure and quantum transport properties
Effect of atomic-scale defects and dopants on phosphorene electronic structure and quantum transport properties
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DOI：
10.1103/physrevb.93.035433
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发表时间：
2016-01
影响因子：
3.7
通讯作者：
A. Lopez-Bezanilla
中科院分区：
文献类型：
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作者：
A. Lopez-Bezanilla
利用多尺度第一性原理方法，描述了具有不同类型修饰的二维窄磷烯片的局部电子结构。首先，基于原始P网络和修正P网络的几何形状，在万尼尔函数形式主义的支持下，引入了一个描述P原子轨道杂化模型的理性论证。从头计算表明，非等电子外来原子在不同能级上形成准束缚态，并根据P与掺杂原子之间的价电子数产生不同的极化态。进一步精确地描述了改性磷烯带的量子输运性质。外源物质在电子带上引起的畸变会对传播中的载流子产生强烈的后向散射效应。根据载流子的能量和掺杂的类型，传导范围可以从扩散到局域。空位上的间隙缺陷导致不同类型掺杂原子间的均匀输运指纹。我们认为，在实验测量中报告的相对较低的电荷迁移率值可能是由于存在缺陷而产生的。
By means of a multiscale first-principles approach, a description of the local electronic structure of two-dimensional and narrow phosphorene sheets with various types of modifications is presented. First, a rational argument based on the geometry of the pristine and modified P network, and supported by the Wannier functions formalism, is introduced to describe a hybridization model of the P atomic orbitals. Ab initio calculations show that nonisoelectronic foreign atoms form quasibound states at varying energy levels and create different polarization states depending on the number of valence electrons between P and the doping atom. The quantum transport properties of modified phosphorene ribbons are further described with great accuracy. The distortions on the electronic bands induced by the external species lead to strong backscattering effects on the propagating charge carriers. Depending on the energy of the charge carrier and the type of doping, the conduction may range from the diffusive to the localized regime. Interstitial defects at vacant sites lead to homogeneous transport fingerprints across different types of doping atoms. We suggest that the relatively low values of charge mobility reported in experimental measurements may have their origin in the presence of defects.