Premium
Nanoimaging of Electronic Heterogeneity in Bi 2 Se 3 and Sb 2 Te 3 Nanocrystals
Author(s) -
Lu Xiaowei,
Khatib Omar,
Du Xutao,
Duan Jiahua,
Wei Wei,
Liu Xianli,
Bechtel Hans A.,
D'Apuzzo Fausto,
Yan Mingtao,
Buyanin Alexander,
Fu Qiang,
Chen Jianing,
Salmeron Miquel,
Zeng Jie,
Raschke Markus B.,
Jiang Peng,
Bao Xinhe
Publication year - 2018
Publication title -
advanced electronic materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.25
H-Index - 56
ISSN - 2199-160X
DOI - 10.1002/aelm.201700377
Subject(s) - materials science , mesoscopic physics , topological insulator , nanocrystal , nanotechnology , scattering , nanomaterials , chemical vapor deposition , chemical physics , condensed matter physics , optics , physics
Topological insulators (TIs) are quantum materials with topologically protected surface states surrounding an insulating bulk. However, defect‐induced bulk conduction often dominates transport properties in most TI materials, obscuring the Dirac surface states. In order to realize intrinsic topological insulating properties, it is thus of great significance to identify the spatial distribution of defects, understand their formation mechanism, and finally control or eliminate their influence. Here, the electronic heterogeneity in polyol‐synthesized Bi 2 Se 3 and chemical vapor deposition‐grown Sb 2 Te 3 nanocrystals is systematically investigated by multimodal atomic‐to‐mesoscale resolution imaging. In particular, by combining the Drude response sensitivity of infrared scattering‐type scanning near‐field optical microscopy with the work‐function specificity of mirror electron microscopy, characteristic mesoscopic patterns are identified, which are related to carrier concentration modulation originating from the formation of defects during the crystal growth process. This correlative imaging and modeling approach thus provides the desired guidance for optimization of growth parameters, crucial for preparing TI nanomaterials to display their intrinsic exotic Dirac properties.