Observation of Plasmarons in Quasi-Freestanding Doped Graphene

被引：360

作者：

Bostwick, Aaron ^{[1
]}

Speck, Florian ^{[2
]}

Seyller, Thomas ^{[2
]}

Horn, Karsten ^{[3
]}

Polini, Marco ^{[4
,5
]}

Asgari, Reza ^{[6
]}

MacDonald, Allan H. ^{[7
]}

Rotenberg, Eli ^{[1
]}

机构：

[1] EO Lawrence Berkeley Lab, ALS, Berkeley, CA 94720 USA

[2] Univ Erlangen Nurnberg, Lehrstuhl Tech Phys, D-91058 Erlangen, Germany

[3] Max Planck Gesell, Fritz Haber Inst, Dept Mol Phys, D-14195 Berlin, Germany

[4] Scuola Normale Super Pisa, I-56126 Pisa, Italy

[5] CNR, Ist Nanosci, I-56126 Pisa, Italy

[6] Inst Res Fundamental Sci, Sch Phys, Tehran 193955531, Iran

[7] Univ Texas Austin, Dept Phys, Austin, TX 78712 USA

来源：

SCIENCE | 2010年 / 328卷 / 5981期

关键词：

D O I：

10.1126/science.1186489

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

A hallmark of graphene is its unusual conical band structure that leads to a zero-energy band gap at a single Dirac crossing point. By measuring the spectral function of charge carriers in quasi-freestanding graphene with angle-resolved photoemission spectroscopy, we showed that at finite doping, this well-known linear Dirac spectrum does not provide a full description of the charge-carrying excitations. We observed composite "plasmaron" particles, which are bound states of charge carriers with plasmons, the density oscillations of the graphene electron gas. The Dirac crossing point is resolved into three crossings: the first between pure charge bands, the second between pure plasmaron bands, and the third a ring-shaped crossing between charge and plasmaron bands.

引用

页码：999 / 1002

页数：4