arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 1012.1382cond-mat.mes-hallcond-mat.mtrl-scicond-mat.str-el
收藏

钾掺杂石墨烯中的声子:电子-声子相互作用、维数和原子有序性的影响

Phonons in potassium doped graphene: the effects of electron-phonon interactions, dimensionality and ad-atom ordering

C. A. Howard, M. P. M. Dean, F. Withers

摘要:

石墨烯声子测量作为电子掺杂的函数,通过添加钾吸附原子。在低掺杂状态下,面内碳G峰随着掺杂的增加而变硬和变窄,类似于经由场效应掺杂的石墨烯中所见的趋势。在高掺杂下,超出场效应可达到的那些,G峰强烈软化和加宽。这被解释为声子自能的动态非绝热重整化。在轻掺杂和重掺杂制度之间的掺杂,我们发现一个强大的不均匀相,其中钾覆盖被隔离成高密度和低密度的区域。1-4层石墨烯的声子能量、线宽和可调谐性非常相似,但与掺杂的块状石墨显著不同。

英文摘要:

Graphene phonons are measured as a function of electron doping via the addition of potassium adatoms. In the low doping regime, the in-plane carbon G-peak hardens and narrows with increasing doping, analogous to the trend seen in graphene doped via the field-effect. At high dopings, beyond those accessible by the field-effect, the G-peak strongly softens and broadens. This is interpreted as a dynamic, non-adiabatic renormalization of the phonon self-energy. At dopings between the light and heavily doped regimes, we find a robust inhomogeneous phase where the potassium coverage is segregated into regions of high and low density. The phonon energies, linewidths and tunability are remarkably similar for 1-4 layer graphene, but significantly different to doped bulk graphite.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑