Effect of Fe-doping on CDW state in 1T-TaS2 investigated by STM/STS

29th International Symposium on Superconductivity

Fujisawa, Y.^1 ; Shimabukuro, T.^1 ; Kojima, H.^1 ; Kobayashi, K.^1 ; Demura, S.^1 ; Sakata, H.^1

Department of Physics, Tokyo University of Science, Shinjuku-ku, Tokyo

162-8601, Japan^1

关键词: Charge density wave state;    Fe doping;    Fe-doped;    Local density of state;    Mott transitions;    Spatial changes;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/871/1/012003/pdf
DOI  :  10.1088/1742-6596/871/1/012003

来源: IOP

【 摘 要 】

1T-TaS2has been known to undergo Mott transition from nearly commensurate charge density wave (CDW) state to commensurate CDW state at about 200 K. Recently, Fe doping was found to suppress the Mott transition and induce superconductivity. In this study, we report on the scanning tunneling microscopy (STM) and spectroscopy (STS) study on Fe doped 1T-TaS2with different Fe concentration. STM observations reveal that the CDW superlattice becomes irregular as increasing Fe concentration. STS measurements uncover the spatial change in the local density of state (LDOS). We find two types of David-star: one has symmetric LDOS with respect to Fermi energy, and the other has asymmetric one. We identify that the asymmetric spectrum is due to an Fe dopant.