| Pacific Rim Symposium on Surfaces, Coatings and Interfaces (PacSurf 2014) | |
| Thin Films | Thursday Sessions |
| Session TF-ThM |
| Session: | Graphene |
| Presenter: | Se-Jong Kahng, Korea University, Republic of Korea |
| Authors: | W.-J. Jang, Korea University, Seoul, Republic of Korea H. Kim, Korea University, Seoul, Republic of Korea M. Wang, Sungkyunkwan University (SKKU), Republic of Korea S.K. Jang, Sungkyunkwan University (SKKU), Republic of Korea M. Kim, SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), Suwon 440-746, Republic of Korea S. Lee, Sungkyunkwan University (SKKU), Republic of Korea S.-W. Kim, Sungkyunkwan University (SKKU), Republic of Korea Y.-J. Song, Sungkyunkwan University (SKKU), Republic of Korea S.-J. Kahng, Korea University, Republic of Korea |
| Correspondent: | Click to Email |
Exotic behaviors such as lensing and perfect transmission are expected in graphene p-n junctions, due to lattice-induced chirality of charge carriers, and experimentally studied using charge transport devices with a scale of several tens of nanometers. However, there has not been a study to confirm such behaviors at the atomic scale. Here, we report the experimental evidence for chiral electron reflections at a graphene junction on hexagonal BN/Cu. We performed scanning tunneling microscopy and spectroscopy to observe unbalanced electron standing wave patterns, which only appeared in one region at an energy lower than 100 meV, or at higher than 250 meV in the other region. Such an energy-dependent crossover of regions of standing wave patterns is explained by solving the Dirac equation with a simple potential step model. Our study shows that chirality of the charge carrier is a key component for understanding their reflections in graphene junctions at the atomic scale.