LAUSR

Here we report the effect of structural and superconductivity properties on Ru-doped $\mathrm{CuI}{\mathrm{r}}_{2}\mathrm{T}{\mathrm{e}}_{4}$ telluride chalcogenide. X-ray diffraction results suggest that $\mathrm{CuI}{\mathrm{r}}_{2\ensuremath{-}x}\mathrm{R}{\mathrm{u}}_{x}\mathrm{T}{\mathrm{e}}_{4}$ maintains the disordered trigonal structure with space group $P\overline{3}m1$ (no. 164) for $x$ \ensuremath{\le} 0.3. The lattice constants, $a$ and $c$, both decrease with increasing Ru content. Temperature-dependent resistivity, magnetic susceptibility, and specific heat measurements are performed to characterize the superconducting properties systematically. Our results suggest that the optimal doping level for superconductivity in $\mathrm{CuI}{\mathrm{r}}_{2\ensuremath{-}x}\mathrm{R}{\mathrm{u}}_{x}\mathrm{T}{\mathrm{e}}_{4}$ is $x=0.05$, where ${T}_{c}$ is 2.79 K with the Sommerfeld constant \ensuremath{\gamma} of $11.52\phantom{\rule{0.16em}{0ex}}\mathrm{mJ}\phantom{\rule{0.16em}{0ex}}\mathrm{mo}{\mathrm{l}}^{\ensuremath{-}1}\phantom{\rule{0.16em}{0ex}}{\mathrm{K}}^{\ensuremath{-}2}$, and the specific heat anomaly at the superconducting transition, $\mathrm{\ensuremath{\Delta}}C/\ensuremath{\gamma}{T}_{c}$, is approximately 1.51, which is slightly higher than the Bardeen-Cooper-Schrieffer value of 1.43 and demonstrates bulk superconductivity in our $\mathrm{CuI}{\mathrm{r}}_{1.95}\mathrm{R}{\mathrm{u}}_{0.05}\mathrm{T}{\mathrm{e}}_{4}$ compound. The values of the lower ${{H}_{c1}(0)}$ and upper ${{H}_{c2}(0)}$ critical field calculated from isothermal magnetization {M(H)} and magnetotransport ${\ensuremath{\rho}(T,H)}$ measurements are 0.98 and 2.47 kOe, respectively, signifying that the compound is clearly a type-II superconductor. Finally, a ``domelike'' shape superconducting transition temperature $({T}_{c})$ vs $x$ content phase diagram has been established. A low substitution ($x=0.03$) of Ru for Ir leads to the disappearance of the charge density wave transition, while ${T}_{c}$ rises and reaches a maximum value of 2.79 K at $x=0.05$, followed by a decrease of ${T}_{c}$ as $x$ increases. This feature of the competition between the charge density wave we have established and the superconductivity could be caused by tuning the Fermi surface and density of states with Ru chemical doping.