Magnetic and Transport Properties in Ion-Irradiated $\text{Cr}_{2}\text{AlC}$

The presence of open-volume defects, such as vacancies, can significantly alter the functional properties of a material, including its structure and electronic transport. This study employs ion irradiation using inert ions
$(\text{Ar}^{+})$
and transition metal ions
$(\text{Co}^{+})$
at fluences of
$10^{12}-10^{15}\text{ions}\cdot \text{cm}^{-2}$
to achieve systematic disorder in the multilayer structure of MAX-phase
$\text{Cr}_{2}\text{AlC}$
. It is shown that the magnitude of the paramagnetic response of
$\text{Cr}_{2}\text{AlC}$
increases with ion fluence, regardless of the dopant used. A combination of isolated moments in defect sites with
$\mathrm{J}={1/2}$
and magnetic clusters are used to explain this behavior. Low-temperature (< 30 K) resistivity measurements show local minima and sudden up(down)-turns with decreasing temperature, which, together with unusual MR in this temperature range, suggest the presence of quantum transport effects, such as the Kondo effect.