Plasmaron

The plasmaron is a quasiparticle that is formed by coupling electrons or holes with plasmons . Plasma ions play a special role in the electronic structure of graphene .

Theoretically, plasmaron was predicted as early as the 1960s; first indications were found in 2007 in elemental bismuth . It was proven in 2010 in graphs at the Lawrence Berkeley National Laboratory ( Advanced Light Source ) through its influence on their band structure . The valence and conduction bands of graphs have the shape of a double cone, the tips of which are on top of each other, so that there is no band gap . Electrons and holes near the tips ( Dirac crossing ) have a low effective mass and easily couple to plasmons. A more detailed analysis of the band structure resulted in a "more blurred" structure similar to the superposition of two double cones, which are slightly shifted against each other. In the experiments to determine the band structure, graphene layers that were as flat as possible were produced by heating silicon carbide and irradiating them with X-ray light from the Advanced Light Source . The spectrum of the released electrons was ARPES ( English angle-resolved photoemission spectroscopy ) investigated.

Web links

Eli Rotenberg Plasmonic promises: first observations of plasmarons in Graphene , Berkeley Lab, May 2010

Individual evidence

↑ BI Lundqvist: Single-particle spectrum of the degenerate electron gas . In: Journal for Physics B: Physics of Condensed Matter . tape 6 , no. 3 , September 1967, p. 193-205 , doi : 10.1007 / BF02422716 .
↑ Riccardo Tediosi, NP Armitage, E. Giannini, D. van der Marel: Charge Carrier Interaction with a Purely Electronic Collective Mode: Plasmarons and the Infrared Response of Elemental Bismuth . In: Physical Review Letters . tape 99 , no. 1 , July 6, 2007, p. 016406 , doi : 10.1103 / PhysRevLett.99.016406 , arxiv : cond-mat / 0701447 .
↑ Aaron Bostwick, Florian Speck, Thomas Seyller, Karsten Horn, Marco Polini, Reza Asgari, Allan H. MacDonald, Eli Rotenberg: Observation of Plasmarons in Quasi-Freestanding Doped Graphene . In: Science . tape 328 , no. 5981 , May 21, 2010, p. 999-1002 , doi : 10.1126 / science.1186489 .
↑ A new “plasmaron” quasiparticle in the spectrum of graphene. Fritz Haber Institute of the Max Planck Society , June 14, 2010, accessed on August 25, 2012 .

[1] BI Lundqvist: Single-particle spectrum of the degenerate electron gas . In: Journal for Physics B: Physics of Condensed Matter . tape 6 , no. 3 , September 1967, p. 193-205 , doi : 10.1007 / BF02422716 .

[2] Riccardo Tediosi, NP Armitage, E. Giannini, D. van der Marel: Charge Carrier Interaction with a Purely Electronic Collective Mode: Plasmarons and the Infrared Response of Elemental Bismuth . In: Physical Review Letters . tape 99 , no. 1 , July 6, 2007, p. 016406 , doi : 10.1103 / PhysRevLett.99.016406 , arxiv : cond-mat / 0701447 .

[3] Aaron Bostwick, Florian Speck, Thomas Seyller, Karsten Horn, Marco Polini, Reza Asgari, Allan H. MacDonald, Eli Rotenberg: Observation of Plasmarons in Quasi-Freestanding Doped Graphene . In: Science . tape 328 , no. 5981 , May 21, 2010, p. 999-1002 , doi : 10.1126 / science.1186489 .

[4] A new “plasmaron” quasiparticle in the spectrum of graphene. Fritz Haber Institute of the Max Planck Society , June 14, 2010, accessed on August 25, 2012 .