石墨烯附着于浅凹陷处的双向应变。

Biaxial strain in graphene adhered to shallow depressions.

机构信息

Department of Physics, 590 Commonwealth Avenue, The Boston University Photonics Center, 8 Saint Mary's Street, Boston University, Boston, Massachusetts 02215, USA.

出版信息

Nano Lett. 2010 Jan;10(1):6-10. doi: 10.1021/nl901625v.

DOI:10.1021/nl901625v

PMID:19928908

Abstract

Measurements on graphene exfoliated over a substrate prepatterned with shallow depressions demonstrate that graphene does not remain free-standing but instead adheres to the substrate despite the induced biaxial strain. The strain is homogeneous over the depression bottom as determined by Raman measurements. We find higher Raman shifts and Gruneisen parameters of the phonons underlying the G and 2D bands under biaxial strain than previously reported. Interference modeling is used to determine the vertical position of the graphene and to calculate the optimum dielectric substrate stack for maximum Raman signal.

摘要

对在具有浅凹陷的基底上外延生长的石墨烯进行的测量表明，尽管存在双轴应变，但石墨烯并未保持自由状态，而是粘附在基底上。拉曼测量表明，应变在凹陷底部是均匀的。我们发现，双轴应变下 G 带和 2D 带的声子的 Raman 位移和 Gruneisen 参数比以前报道的要高。干涉建模用于确定石墨烯的垂直位置，并计算用于获得最大 Raman 信号的最佳介电基底堆叠。