TY  - JOUR
AU  - Neumann, Christoph
AU  - Banszerus, Luca
AU  - Schmitz, Michael
AU  - Reichardt, Sven
AU  - Sonntag, Jens
AU  - Taniguchi, Takashi
AU  - Watanabe, Kenji
AU  - Beschoten, Bernd
AU  - Stampfer, Christoph
TI  - Line shape of the Raman 2D peak of graphene in van der Waals heterostructures
JO  - Physica status solidi / B
VL  - 253
IS  - 12
SN  - 0370-1972
CY  - Weinheim
PB  - Wiley-VCH70889
M1  - FZJ-2017-02569
SP  - 2326-2330
PY  - 2016
AB  - The Raman 2D line of graphene is widely used for device characterization and during device fabrication as it contains valuable information on, e.g., the direction and magnitude of mechanical strain and doping. Here, we present systematic asymmetries in the 2D line shape of exfoliated graphene and graphene grown by chemical vapor deposition. Both graphene crystals are fully encapsulated in van der Waals heterostructures, where hexagonal boron nitride and tungsten diselenide are used as substrate materials. In both material stacks, we find very low doping values and extremely homogeneous strain distributions in the graphene crystal, which is a hall mark of the outstanding electronic quality of these samples. By fitting double Lorentzian functions to the spectra to account for the contributions of inner and outer processes to the 2D peak, we find that the splitting of the sub-peaks, math formulacm−1 (hBN-Gr-WSe2) and math formulacm−1 (hBN-Gr-hBN), is significantly lower than the values reported in previous studies on suspended graphene.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000390339000005
DO  - DOI:10.1002/pssb.201600283
UR  - https://juser.fz-juelich.de/record/828677
ER  -