| 引用本文格式: Xu Zhong-Hui,Zhao Shu-Liang,Wang Li-Feng,Liu Chuan-Chuan. First-Principles study on Photoelectric Effect of doping Effects on Monolayer 2H-MoTe2 [J]. J. At. Mol. Phys., 2024, 41(3): 036005 (in Chinese) [徐中辉,赵书亮,王利峰,刘川川. 掺杂对2H-MoTe2光电特性影响的第一性原理研究 [J]. 原子与分子物理学报, 2024, 41(3): 036005] |
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| 掺杂对2H-MoTe2光电特性影响的第一性原理研究 |
| First-Principles study on Photoelectric Effect of doping Effects on Monolayer 2H-MoTe2 |
| 摘要点击 95 全文点击 21 投稿时间：2022-10-30 修订日期：2022-11-29 |
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| DOI编号
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| 中文关键词
2H-MoTe2 光电效应 掺杂 第一性原理 光电探测器 |
| 英文关键词
2H-MoTe2 photogalvanic effect doping first principle photodetector |
| 基金项目
国家自然科学基金 |
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| 中文摘要
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| MoTe2是一种非空间反演对称性半导体，由线性偏振光照射，在无偏压条件下可以直接产生光电流，但是非常微弱。掺杂可以改变电子能带结构和降低空间反演对称性，从而有效的增强光电流。本文基于非平衡格林函数-密度泛函理论，采用第一性原理，计算了本征、Nb掺杂、Ti掺杂和W掺杂2H-MoTe2的能带结构、透射谱和光电流。能带结构表明：Nb掺杂使半导体2H-MoTe2能带穿越费米能级，转变为金属特性；Ti和W掺杂减小了2H-MoTe2的带隙，能带没有穿越费米能级，依然为半导体。掺杂都降低2H-MoTe2的反演对称对称性，从本征的D3h转变为Cs。从而在线偏振光的照射下可以有效的提高2H-MoTe2的光电流。同时，发现掺杂可以提高单层2H-MoTe2在低光子能量下的消光比，如Nb和Ti掺杂单层2H-MoTe2分别在光子能量1.1 eV和1.2 eV处取得39.48和28.48的高消光比。这些结果表明掺杂可以有效增强单层2H-MoTe2的光电流和消光比，可以应用于指导2H-MoTe2在光电器件的设计,特别是在红外光探测邻域增添了许多可能。 |
| 英文摘要
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| MoTe2 is a non-spatial inversion symmetric semiconductor, which is illuminated by linearly polarized light and can directly generate photocurrent without bias, but it is very weak. Doping can change the electronic band structure and reduce the spatial inversion symmetry, thus effectively enhancing the photocurrent. Based on the non-equilibrium Green's function-density functional theory, the band structure, transmission spectrum and photocurrent of intrinsic, Nb-, Ti- and W- doped 2H-MoTe2 are calculated using the first principles. The energy band structure shows that Nb doping makes the energy band of the semiconductor 2H-MoTe2 pass through the Fermi level and change into a metal property. Ti- and W- doping reduced the band gap of 2H-MoTe2, and the band did not cross the Fermi level, so it was still a semiconductor. Doping decreases the inversion symmetry of 2H-MoTe2 and transforms from intrinsic D3h to Cs. Thus, the photocurrent of 2H-MoTe2 can be effectively improved under the irradiation of linearly polarized light. At the same time, it is found that doping can improve the extinction ratio of monolayer 2H-MoTe2 at low photon energy, for example, Nb and Ti doped monolayer 2H-MoTe2 achieve 39.48 and 28.48 high extinction ratios at 1.1 eV and 1.2 eV of photon energy, respectively. These results show that doping can effectively enhance the photocurrent and extinction ratio of single monolayer 2H-MoTe2,and can be used to guide the design of 2H-MoTe2 in photoelectric devices, especially in the infrared light detection neighborhood. |
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