STM Image of Sub-surface Impurities in 1T-TaS_2
Abstract
It was found that the STM image of sub-surface impurities in 1T-TaS2 was drastically changed with respect to the NC-CDW to C-CDW phase transition, which also drives the Mott localization in C-CDW. In the high temperature (NC-CDW) phase, impurities was seen as dark spots with a dimension of 1 nm, while oscillating structures with lateral and vertical sizes of 10 nm and 1 nm, respectively, was observed in the low temperature (C-CDW) phase. Recent theoretical approach(K. Kobayashi, Phys. Rev. B, in press.) demonstrated that the oscillating structure appears on the STM image, only when the wavelength of electrons is larger than the decay length of the screened Coulomb potential around an impurity. The drastic change of impurity image observed in the present study is possibly triggered by the band splitting at the phase transition point.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 1997
- Bibcode:
- 1997APS..MAR.B1711H