Adsorbate-induced pinning of a charge-density wave in a quasi-1D metallic chains: Na on the In/Si(111)-(4x1) surface.
We find that foreign adsorbates acting as local impurities can induce a metal-insulator transition by pinning a charge-density wave (CDW) on the quasi-1D metallic In/Si(111)-(4x1) chain system. Our scanning tunneling microscopy image clearly reveals the presence of a new local 4x2 structure nucleated by Na adatoms at room temperature, which turns out to be insulating with a doubled periodicity along the chains. We directly determine a CDW gap energy Delta = 105+/-8 meV by identifying a characteristic loss peak in our high-resolution electron-energy-loss spectra. We thus report the first observation of a local impurity-derived Peierls-like reconstruction of a quasi-1D system.
Lee
S S
SS
Physics Department and Basic Science Research Institute, Pohang University of Science and Technology, San 31 Hyoja Dong, Pohang 790-784, Korea.
Ahn
J R
JR
Kim
N D
ND
Min
J H
JH
Hwang
C G
CG
Chung
J W
JW
Yeom
H W
HW
Ryjkov
Serguei V
SV
Hasegawa
Shuji
S