TY - JOUR
T1 - Highly Conductive Metallic State and Strong Spin-Orbit Interaction in Annealed Germanane
AU - Chen, Qihong
AU - Liang, Lei
AU - Potsi, Georgia
AU - Wan, Puhua
AU - Lu, Jianming
AU - Giousis, Theodosis
AU - Thomou, Eleni
AU - Gournis, Dimitrios
AU - Rudolf, Petra
AU - Ye, Jianting
N1 - Funding Information:
We thank J. Harkema, A. Joshua, and J. Zoestbergen for technical support. Q. Chen thanks the scholarship from The Ubbo Emmius Fund. J. Ye and Q. Chen thank the Stichting voor Fundamenteel Onderzoek der Materie (FOM, FV157) and FlagERA iSpinText for financial support. J. Ye acknowledges funding from the European Research Council (consolidator Grant No. 648855, Ig-QPD).
Publisher Copyright:
© 2019 American Chemical Society.
Copyright:
Copyright 2019 Elsevier B.V., All rights reserved.
PY - 2019/3
Y1 - 2019/3
N2 - Similar to carbon, germanium exists in various structures such as three-dimensional crystalline germanium and germanene, a two-dimensional germanium atomic layer. Regarding the electronic properties, they are either semiconductors or Dirac semimetals. Here, we report a highly conductive metallic state in thermally annealed germanane (hydrogen-terminated germanene, GeH), which shows a resistivity of similar to 10(-7) Omega.m that is orders of magnitude lower than any other allotrope of germanium. By comparing the resistivity, Raman spectra, and thickness change measured by AFM, we suggest the highly conductive metallic state is associated with the dehydrogenation during heating, which likely transforms germanane thin flakes to multilayer germanene. In addition, weak antilocalization is observed, serving as solid evidence for strong spin-orbit interaction (SOI) in germanane/germanene. Our study opens a possible new route to investigate the electrical transport properties of germanane/germanene, and the large SOI might provide the essential ingredients to access their topological states predicted theoretically.
AB - Similar to carbon, germanium exists in various structures such as three-dimensional crystalline germanium and germanene, a two-dimensional germanium atomic layer. Regarding the electronic properties, they are either semiconductors or Dirac semimetals. Here, we report a highly conductive metallic state in thermally annealed germanane (hydrogen-terminated germanene, GeH), which shows a resistivity of similar to 10(-7) Omega.m that is orders of magnitude lower than any other allotrope of germanium. By comparing the resistivity, Raman spectra, and thickness change measured by AFM, we suggest the highly conductive metallic state is associated with the dehydrogenation during heating, which likely transforms germanane thin flakes to multilayer germanene. In addition, weak antilocalization is observed, serving as solid evidence for strong spin-orbit interaction (SOI) in germanane/germanene. Our study opens a possible new route to investigate the electrical transport properties of germanane/germanene, and the large SOI might provide the essential ingredients to access their topological states predicted theoretically.
KW - dehydrogenation
KW - Germanane
KW - metallic state
KW - multilayer germanene
KW - strong spin-orbit interaction
KW - weak antilocalization
UR - http://www.scopus.com/inward/record.url?scp=85061894592&partnerID=8YFLogxK
U2 - 10.1021/acs.nanolett.8b04207
DO - 10.1021/acs.nanolett.8b04207
M3 - Article
C2 - 30674194
SN - 1530-6984
VL - 19
SP - 1520
EP - 1526
JO - Nano Letters
JF - Nano Letters
IS - 3
ER -