resumo
Ferroelectric materials with tailored domain structures are promising smart substrates providing additional degrees of functionality for the graphene-based devices. We demonstrate the effect of periodical domain structure in lithium niobate substrate on the electrical properties of graphene studied by Raman spectroscopy. The spatial variations of the charge carriers and Fermi levels in graphene corresponding to oppositely polarized domains have been elucidated. The observed effects are supposed to be driven by the lateral component of electric field at the surface related to the gradient of spontaneous polarization. The five orders of magnitude decay of charge density in graphene is due to screening of depolarization field.
palavras-chave
STRONG PIEZOELECTRICITY; RAMAN
categoria
Materials Science; Physics
autores
Zelenovskii, P; Romanyuk, K; Vidyasagar, R; Akhmatkhanov, A; Zhao, P; Shur, VY; Kholkin, AL
nossos autores
Andrei Kholkin
Investigador Principal
Pavel Zelenovskii
Investigador
Reddithota Vidyasagar
Bolseiro de pós-DoutoramentoGrupos
G2 - Materiais Fotónicos, Eletrónicos e Magnéticos
G3 - Materiais Eletroquímicos, Interfaces e Revestimentos
agradecimentos
The authors are grateful to the Russian Foundation for Basic Research (grant No 16-29-14050-ofr-m) and Government of the Russian Federation (Act 211, Agreement 02.A03.21.0006) for the financial support. VS and AA are grateful for financial support of the Ministry of Science and Higher Education of the Russian Federation (state tasks 3.4993.2017/6.7 and 3.4973.2017/7.8). RV thanks Fundacao para a Ciencia e Tecnologia (FCT) for the Grant SFRH/BPD/104887/2014. KR thanks FCT for the grant SFRH/BPD/88362/2012. The authors from University of Aveiro acknowledge CICECO-Aveiro Institute of Materials (Ref. FCT UID/CTM/50011/2019) financed by the national funds through the FCT/MEC. The equipment of Ural Center for Shared Use Modern Nanotechnologies UrFU was used.