TY - JOUR
T1 - Insulating conduction in Sn/Si(111)
T2 - Possibility of a Mott insulating ground state and metallization/localization induced by carrier doping
AU - Hirahara, Toru
AU - Komorida, Taku
AU - Gu, Yan
AU - Nakamura, Fumitaka
AU - Idzuchi, Hiroshi
AU - Morikawa, Harumo
AU - Hasegawa, Shuji
PY - 2009/12/11
Y1 - 2009/12/11
N2 - The transport properties of the Si (111) √3×√3-Sn surface are investigated by micro-four-point-probe conductivity measurements. The temperature dependence of the surface-state conductivity showed an insulating behavior from room temperature down to 15 K although the surface was believed to be metallic. Furthermore, with changing the band filling by partially replacing Sn atoms with In or Na deposition, we found that the conductivity showed a metallic behavior down to 260 K and upon further cooling, the carriers became strongly localized possibly due to the dopants themselves. Our result suggests that the ground state of this surface is insulating with a very small energy gap, which is consistent with a recent theoretical study predicting this surface to be a Mott insulator.
AB - The transport properties of the Si (111) √3×√3-Sn surface are investigated by micro-four-point-probe conductivity measurements. The temperature dependence of the surface-state conductivity showed an insulating behavior from room temperature down to 15 K although the surface was believed to be metallic. Furthermore, with changing the band filling by partially replacing Sn atoms with In or Na deposition, we found that the conductivity showed a metallic behavior down to 260 K and upon further cooling, the carriers became strongly localized possibly due to the dopants themselves. Our result suggests that the ground state of this surface is insulating with a very small energy gap, which is consistent with a recent theoretical study predicting this surface to be a Mott insulator.
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U2 - 10.1103/PhysRevB.80.235419
DO - 10.1103/PhysRevB.80.235419
M3 - Article
AN - SCOPUS:77954719387
VL - 80
JO - Physical Review B - Condensed Matter and Materials Physics
JF - Physical Review B - Condensed Matter and Materials Physics
SN - 0163-1829
IS - 23
M1 - 235419
ER -