Evolution of the Charge Density Wave state in Cu$_x$TiSe$_2$

ORAL

Abstract

1T-TiSe$_2$ is a quasi two-dimensional CDW material showing a 2x2x2 superlattice modulation below 200 K. Upon Cu doping the CDW is suppressed and superconductivity is induced. We present scanning tunneling microscopy and spectroscopy measurements of the charge-density wave state in 1T-TiSe$_2$, Cu$_{0.05}$TiSe$_2$ and Cu$_{0.06}$TiSe$_2$ single crystals. Topography images at 4.2 K reveal that the charge density waves are present in all samples studied, although the amplitude of the charge modulation decreases with the Cu-doping. Moreover, the chiral phase of the charge density wave is preserved also in Cu-doped samples. Tunneling spectroscopy shows that there is only a partial gap in the pure compound, with bands crossing the Fermi surface. In the Cu-doped samples the system becomes more metallic due to the increase of the chemical potential.

*This work was supported by US DOE Grant No. DE-FG02-10ER46710.

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Authors

  • Maria Iavarone

    • Physics Department, Temple University, Philadelphia, PA 19122 USA
    • Temple University
    • Physics Department, Temple University, Philadelphia, PA 19122, USA

  • Roberto Di Capua

    • Physics Department, Temple University, Philadelphia, PA 19122, USA

  • Xin Zhang

    • Physics Department, Temple University, Philadelphia, PA 19122, USA

  • Maryam Golalikhani

    • Physics Department, Temple University, Philadelphia, PA 19122, USA

  • Steven Moore

    • Physics Department, Temple University, Philadelphia, PA 19122 USA
    • Physics Department, Temple University, Philadelphia, PA 19122, USA

  • Goran Karapetrov

    • Physics Department, Drexel University, Philadelphia, PA 19104 USA
    • Physics Department, Drexel University
    • Drexel University
    • Physics Department, Drexel University, Philadelphia PA 19104, USA
    • Department of Physics, Drexel University and Institute of Electrical Engineering, Slovak Academy of Sciences