Moraes Elizane E de, Coutinho-Filho Maurício D, Batista Ronaldo J C
Laboratório de Física Teórica e Computacional, Departamento de Física, Universidade Federal de Pernambuco, Cidade Universitária, 50670-901 Recife, Pernambuco, Brazil.
Departamento de Física, Universidade Federal de Ouro Preto, Campus Morro do Cruzeiro s/n, 35400-000 Ouro Preto, Minas Gerais, Brazil.
ACS Omega. 2017 Apr 27;2(4):1696-1701. doi: 10.1021/acsomega.7b00061. eCollection 2017 Apr 30.
The electrical transport properties of a four-layered hydrogen-terminated cubic boron nitride sub-nanometer film in contact with gold electrodes are investigated via density functional calculations. The sample exhibits surfaces, a fundamental feature that triggers the system to behave like a typical p-n junction diode for voltage bias in the interval -0.2 ≤ ≤ 0.2, where a rectification ratio up to 62 is verified. Further, in the wider region -0.3 ≤ ≤ 0.3, negative differential resistance with a peak-to-valley ratio of 10 is observed. The qualitative behavior of the - characteristics is described in terms of the hydrogenated cBN film equilibrium electronic structure. Such a film shows metallic surfaces due to surface electronic states at a fraction of eV above and below the Fermi level of the N-H terminated and B-H terminated surfaces, respectively, with a wide bulk-band gap characteristic of BN materials. Such a mechanism is supported by transmission coefficient calculations, with the Landauer-Büttiker formula governing the characteristics.
通过密度泛函计算研究了与金电极接触的四层氢终止立方氮化硼亚纳米薄膜的电输运性质。该样品呈现出一些表面特性，这一基本特征使得系统在 -0.2 ≤ ≤ 0.2 的电压偏置区间内表现得像一个典型的 p-n 结二极管，在此区间验证了高达 62 的整流比。此外，在更宽的 -0.3 ≤ ≤ 0.3 区域内，观察到具有 10 的峰谷比的负微分电阻。I-V 特性的定性行为是根据氢化立方氮化硼薄膜的平衡电子结构来描述的。这种薄膜由于分别在 N-H 终止表面和 B-H 终止表面的费米能级上下几分之一电子伏特处存在表面电子态而呈现出金属表面，同时具有立方氮化硼材料典型的宽体带隙。这种机制得到了传输系数计算的支持，由朗道尔-布蒂克尔公式支配 I-V 特性。
