High-energy collective electronic excitations in free-standing single-layer graphene
High-energy collective electronic excitations in free-standing single-layer graphene
复制标题
独立式单层石墨烯中的高能集体电子激发
DOI：
10.1103/physrevb.88.075433
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发表时间：
2013
影响因子：
3.7
通讯作者：
Kaiser U
中科院分区：
文献类型：
--
作者：
Wachsmuth P;Hambach R;Kinyanjui MK;Guzzo M;Benner G;Kaiser U
在这项联合实验和理论工作中，我们研究了独立的单层石墨烯中的集体电子激发(等离子激子)。在透射电子显微镜中，用动量分辨电子能量损失谱测量了第一布里渊区沿两个独立的面内对称方向的能量和动量相关的电子能量损失函数。我们将实验结果与相应的含时密度泛函理论计算结果进行了比较。对于有限动量转移，如果考虑晶体的局域场效应，则与实验符合得很好。在小的动量转移和零动量转移的极限下，我们讨论了有限动量分辨和平面外激发引起的石墨烯的电子能量损失函数与计算结果之间的差异。
In this joint experimental and theoretical work, we investigate collective electronic excitations (plasmons) in free-standing, single-layer graphene. The energy- and momentum-dependent electron energy-loss function was measured up toalong two independent in-plane symmetry directions (and) over the first Brillouin zone by momentum-resolved electron energy-loss spectroscopy in a transmission electron microscope. We compare our experimental results with corresponding time-dependent density-functional theory calculations. For finite momentum transfers, good agreement with experiments is found if crystal local-field effects are taken into account. In the limit of small and vanishing momentum transfers, we discuss differences between calculations and the experimentally obtained electron energy-loss functions of graphene due to a finite momentum resolution and out-of-plane excitations.
DOI：
--
发表时间：
2011
期刊：
--
影响因子：
--
作者：
M. Rosseinsky
通讯作者：
M. Rosseinsky