Point-contact tunneling spectroscopy measurement of Cu$_x$TiSe$_2$:   disorder-enhanced Coulomb effects
  We performed point-contact spectroscopy tunneling measurements on Cu$_x$TiSe$_2$ bulk with $x=0.02$ and $0.06$ at temperatures ranging from $T=4-40$ K and observe a suppression in the density of states around zero-bias that we attribute to enhanced Coulomb interactions due to disorder. We find that the correlation gap associated with this suppression is related to the zero-temperature resistivity. We use our results to estimate the disorder-free transition temperature and find that the clean limit $T_{c0}$ is close to the experimentally observed $T_c$. 
Katherine Luna, Phillip M. Wu, Justin S. Chen, Emilia Morosan, Malcolm   R. Beasley
cond-mat.supr-con