Electronic coupling in the F4-TCNQ/single-layer GaSe heterostructure
Electronic coupling in the F4-TCNQ/single-layer GaSe heterostructure
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DOI：
10.1103/physrevmaterials.3.084002
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发表时间：
2019-08
影响因子：
3.4
通讯作者：
L. Khalil;D. Pierucci;E. Papalazarou;J. Chaste;M. Silly;F. Sirotti;M. Eddrief;L. Perfetti;E. Lhuillier;A. Ouerghi
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文献类型：
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作者：
L. Khalil;D. Pierucci;E. Papalazarou;J. Chaste;M. Silly;F. Sirotti;M. Eddrief;L. Perfetti;E. Lhuillier;A. Ouerghi
由吸附在二维金属单硫族化物上的有机分子制成的混合异质结构通常揭示了改善单个本构层的电子性质的界面效应。在这里，我们研究了F4-TCNQ/单层GaSe异质结的界面电子特性。获得了F_4-TCNQ/GaSe尖锐的界面，并用X射线光电子能谱对其进行了表征。我们表明，高电子转移从1 TL的GaSe到吸附的F4-TCNQ分子发生，从而产生的过量的负电荷密度的GaSe的减少。此外，异质结构的直接能带结构的测定已经进行了使用角分辨光电子能谱，脱落光的基本功能，如掺杂和带偏移的接口。我们的结果表明，在F4-TCNQ层下面的掩埋1 TL GaSe在Γ点处表现出强烈的价色散反转，形成深度为120 ± 10 meV的墨西哥帽形色散。我们的实验还表明，F4-TCNQ可以显着地调整1 TL GaSe的电子性质，通过移动约0.16 eV的带偏移向较低的结合能相对于费米能级，这是一个关键的功能设想其在纳米电子学中的应用。
Hybrid heterostructures, made of organic molecules adsorbed on two-dimensional metal monochalcogenide, generally unveil interfacial effects that improve the electronic properties of the single constitutive layers. Here, we investigate the interfacial electronic characteristics of the F4-TCNQ/single layer GaSe heterostructure. A sharp F4-TCNQ/GaSe interface has been obtained and characterized by X-ray photoemission spectroscopy. We demonstrate that a high electron transfer from 1TL GaSe into the adsorbed F4-TCNQ molecules takes place, thereby yielding a reduction in the excess negative charge density of GaSe. Additionally, the direct band structure determination of the heterostructure has been carried out using angle-resolved photoemission spectroscopy, shedding light on essential features such as doping and band offset at the interface. Our results indicate that the buried 1TL GaSe bellow the F4-TCNQ layer exhibits a robust inversion of the valence dispersion at the Γ point, forming a Mexican-hat-shaped dispersion with 120 ± 10 meV of depth. Our experiments also reveal that F4-TCNQ can significantly tune the electronic properties of 1TL GaSe by shifting the band offset of about 0.16 eV toward lower binding energies with respect to the Fermi level, which is a key feature for envisioning its applications in nanoelectronics.