不同电极构型的砷烯和砷化锑扩展分子的电子输运性质  

Electron Transport Properties of Arsenene and Antimony Arsenide Extended Molecules with Different Electrode Configurations

作　　者：杨亚杰 苏文勇[1] 衡成林[1] 王锋 YANG Yajie;SU Wenyong;HENG Chenglin;WANG Feng(School of Physics,Beijing Institute of Technology,Beijing 100081,China)

机构地区：[1]北京理工大学物理学院,北京100081

出　　处：《材料导报》2020年第18期18039-18043,共5页Materials Reports

基　　金：国家自然科学基金(61775016,11774030,11374033,51735001)。

摘　　要：通过杂化密度泛函理论和弹性散射格林函数方法,计算了不同电极结构的Au-As-Au和Au-AsSb-Au扩展分子的电子输运性质。结果表明,在两种Au-As-Au扩展分子中,类型Ⅰ扩展分子容易导通,并在0.5 V时达到较宽的3.8 nA饱和电流;类型Ⅱ扩展分子在0.4 V之前几乎没有电流,之后缓慢增加并在1.5 V达到与类型Ⅰ相同的饱和电流。这说明不同的电极接触方式改变了砷烯扩展分子的分子轨道性质,但是并未改变它们的最大电流导通能力。在两种Au-AsSb-Au扩展分子中,类型Ⅰ扩展分子容易导通并在0.5 V时达到较宽的1.8 nA饱和电流;类型Ⅱ扩展分子在1.0 V之前电流增加缓慢,之后迅速增加并在1.25 V达到1.0 nA饱和电流。对比发现,类型Ⅰ扩展分子容易导通且具有较宽的电流平台值;类型Ⅱ扩展分子不易导通,之后会达到一个较窄的电流平台值,这使砷类分子器件具备了更丰富的电子输运性质,从而在电路中满足稳恒输出、阈值开关、线性响应的不同要求。The electron transport properties of Au-As-Au and Au-As Sb-Au extended molecules with different electrode structures were calculated by hybrid density functional theory and elastic scattering Green function method. The results show that,among two Au-As-Au extended molecules,type Ⅰ extended molecule is easy to conduct and reaches a wide saturation current of 3. 8 n A at 0. 5 V;type Ⅱ extended molecule has almost no current before 0. 4 V,then increases slowly and reaches the same saturation current as type Ⅰ at 1. 5 V. This shows that different electrode contact methods change the orbital characteristics of arsenic extended molecules,but don’t change their maximum current conducting ability. Among two Au-As Sb-Au extended molecules,type I extended molecule is easy to conduct and reaches a wide saturation current of 1. 8 n A at0. 5 V;type Ⅱ extended molecule increases slowly before 1. 0 V,then increases rapidly after 1. 25 V and reaches 1. 0 n A saturation current. Finally,it is found that type Ⅰ extended molecule is easy to conduct and has a wide current plateau value,while type II extended molecule is not easy to conduct and has a narrow current plateau value,which make arsenic molecular devices have more electron transport properties,to meet the different requirements of steady current output,threshold switch,linear response.

关 键 词：砷烯 砷化锑 电子输运 饱和电流 阈值开关 

分 类 号：O469[理学—凝聚态物理]