Dirac charge dynamics in graphene by infrared spectroscopy

By Zhiqiang Li, E. Henriksen, Zhigang Jiang, Z. Hao, Michael C. Martin, Philip Kim, H. Stormer, D. Basov. 2008

1,107 citations recorded by the source corpus.

A remarkable manifestation of the quantum character of electrons in matter is offered by graphene, a single atomic layer of graphite. Unlike conventional solids where electrons are described with the Schrodinger equation, electronic excitations in graphene are governed by the Dirac hamiltonian. Some of the intriguing electronic properties of graphene, such as massless Dirac quasiparticles with linear energy-momentum dispersion, have been confirmed by recent observations. Here, we report an infrared spectromicroscopy study of charge dynamics in graphene integrated in gated devices. Our measurements verify the expected characteristics of graphene and, owing to the previously unattainable accuracy of infrared experiments, also uncover significant departures of the quasiparticle dynamics from predictions made for Dirac fermions in idealized, free-standing graphene. Several observations reported here indicate the relevance of many-body interactions to the electromagnetic response of graphene.

Subfields: Atomic and Molecular Physics, and Optics, Materials Chemistry

View Paper: https://www.semanticscholar.org/paper/5018636095a0ae0fde5e29f42d0a710803070f7f

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Atomic and Molecular Physics, and Optics

1. N. M. R. Peres
2. K. Novoselov
3. E. Rossi
4. E. Hwang
5. S. Adam
6. Feng Wang
7. D. Basov
8. Yuanbo Zhang

In Materials Chemistry

1. K. Novoselov
2. N. M. R. Peres
3. E. Hwang
4. E. Rossi
5. Phaedon Avouris
6. S. Adam
7. Feng Wang
8. D. Basov

Citations in the corpus

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