Work

Lamb shift of the Dirac cone of graphene

Year: 2016

Type: article

Abstract: The fluctuations of the electromagnetic vacuum are one of the most powerful manifestations of the quantum structure of nature. Their effect on the Dirac electrons of graphene is known to induce some spectacular and purely quantistic phenomena, like the Casimir and the Aharanov-Bohm effects. In this work we demonstrate, by using a first-principles approach, that the Dirac cone of graphene is also affected by a sizeable Lamb shift. We show that the microscopic electronic currents flowing on the graphene plane are strongly coupled with the vacuum fluctuations causing a renormalisation of the electronic levels (as large as 4 meV). This shift is one order of magnitude larger than the value predicted for an isolated carbon atom, which imposes a reinterpretation of the Lamb shift as a collective effect.

Source: Europhysics Letters (EPL)

DOI: 10.1209/0295-5075/116/43001

Authors: Pedro Miguel M. C. de Melo, Andrea Marini

Institutions: Institute of Structure of Matter, National Research Council, Centro de Física da Universidade de Coimbra, University of Coimbra, European Theoretical Spectroscopy Facility

Language: English

Topic: Quantum Electrodynamics and Casimir Effect

Subfield: Atomic and Molecular Physics, and Optics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green

Funders: European Commission, Ministero dell’Istruzione, dell’Università e della Ricerca, Horizon 2020 Framework Programme, Fundação para a Ciência e a Tecnologia