Mass-related inversion symmetry breaking and phonon self-energy renormalization in isotopically labeled AB-stacked bilayer graphene

0421293 - ÚFCH JH 2014 RIV GB eng J - Článek v odborném periodiku
Araujo, P. T. - Frank, Otakar - Mafra, D. L. - Fang, W. - Kong, J. - Dresselhaus, M. S. - Kalbáč, Martin
Mass-related inversion symmetry breaking and phonon self-energy renormalization in isotopically labeled AB-stacked bilayer graphene.
Scientific Reports. Roč. 3, JUN 2013 (2013), s. 2061. ISSN 2045-2322. E-ISSN 2045-2322
Grant CEP: GA MŠMT LH13022; GA ČR(CZ) GAP208/12/1062
Institucionální podpora: RVO:61388955
Klíčová slova: WALLED CARBON NANOTUBES * RAMAN-SPECTROSCOPY * CHARGE-TRANSFER
Kód oboru RIV: CF - Fyzikální chemie a teoretická chemie
Impakt faktor: 5.078, rok: 2013

A mass-related symmetry breaking in isotopically labeled bilayer graphene (2LG) was investigated during in-situ electrochemical charging of AB stacked (AB-2LG) and turbostratic (t-2LG) layers. The overlap of the two approaches, isotopic labeling and electronic doping, is powerful tool and allows to tailor, independently and distinctly, the thermal-related and transport-related phenomena in materials, since one can impose different symmetries for electrons and phonons in these systems. Variations in the system's phonon self-energy renormalizations due to the charge distribution and doping changes could be analyzed separately for each individual layer. Symmetry arguments together with first-order Raman spectra show that the single layer graphene (1LG), which is directly contacted to the electrode, has a higher concentration of charge carriers than the second graphene layer, which is not contacted by the electrode. These different charge distributions are reflected and demonstrated by different phonon self-energy renormalizations of the G modes for AB-2LG and for t-2LG.
Trvalý link: http://hdl.handle.net/11104/0227705