Speaker
Description
The layered ThCr$_2$Si$_2$-type tetragonal compound, SrCo$_2$As$_2$ shows antiferromagnetic fluctuations, which are believed to be a precursor for superconductivity in the iron-arsenide family. However, the co-existence of ferromagnetic (FM) fluctuations likely precludes a superconducting ground state in this compound. Hence, it is important to investigate whether chemical doping suppresses FM fluctuations in order to reach a superconducting phase. We report here the effect of hole doping on structural, magnetic, and transport properties of high-quality single crystals of SrCo$_2$As$_2$ via partial substitution of Co by Cr. All the doped compositions crystallize remain in ThCr$_2$Si$_2$-type structure. The basal plane electrical resistivity ρab shows metallic behavior for all the doped compositions. The heat capacity $C_{\rm p}(T)$ and magnetic susceptibility $\chi(T)$ of the doped compositions infer the absence of long-range magnetic ordering down to 1.8 K . Sommerfeld coefficient obtained from low-temperature $C_{\rm p}(T)$ data decreases with an increase in Cr concentration, indicating the reduction of the density of states at the Fermi level $E_{\rm F}$. The $\chi_{ab}(T)$ ($H \parallel ab$-plane) and $\chi_{c}(T)$ ($H \parallel c$-axis) are anisotropic and the isothermal magnetization M is proportional to $H$ for both orientations of the applied field. We provide a detailed overview of the dependence of physical properties and electronic states with changes in carrier concentration.
| Apply for student award at which level: | None |
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| Consent on use of personal information: Abstract Submission | Yes, I ACCEPT |
