We study superconducting properties of highly underdoped Cu_{0.058}TiSe_{2} single crystal by means of bulk magnetization measurements. We extract the upper critical field, H_{c2}, for magnetic field applied parallel, as well as perpendicular to the sample planes. Obtained values, H^{ab}_{c2}(0)=1.03 T and H^c_{c2}(0)=0.54 T, define a moderate anisotropy of the upper critical fields of 1.90. From the upper and lower critical fields we extract the Ginzburg-Landau parameters κ_{ab}(0)=26.3, and κ_c(0)=12.6 that classify Cu_{0.058}TiSe_{2} as an extreme type II superconductor.
In TiSe_{2} a charge-density-waves order is continuously suppressed by copper doping and superconductivity appears. We report a calorimetric study performed on the superconducting single crystal of Cu_{0.061}TiSe_{2} with T_{c}=2.8 K, measured by the ac technique at low temperatures down to 0.6 K and magnetic fields up to 2 T. Sharp specific heat anomaly at the superconducting transition is found. The temperature dependence of the electronic specific heat and the angular dependence of the critical temperature, measured at a fixed magnetic field, consistently indicate on the existence of a single s-wave superconducting gap with a coupling strength of 2Δ/k_{B}T_{c}=3.6, close to BCS limit.
Local magnetometry using miniature Hall-probe array was used to study vortex distribution in superconducting single crystal of Cu_{x}TiSe_{2}, with x=0.064 and T_{c}=3.2 K. We show that vortices after penetration into the sample move towards the center, resulting into a dome-shape field profile. Such a profile is a signature of relatively low pinning. We show that these measured profiles are consistent with a model proposed for the samples in the absence of bulk pinning. Modifications necessary to obtain quantitative agreement between the model and the data are presented.
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