Publications Repository - Helmholtz-Zentrum Dresden-Rossendorf

Nano-lamellar composite materials, known as MAX-phases, can possess a combination of ceramic and metallic properties. A prototype compound is Cr2AlC, formed from a unit cell of Cr2C sandwiched between atomic planes of Al. In this work we study the modifications to the structural, transport and magnetic behavior of 500 nm thick Cr2AlC after irradiation with Co+ ions, and Ar+ noble gas ions as control. X-ray diffraction shows that ion-irradiation induces a suppression of the 0002 reflection, indicating a deterioration of the crystal structure. Increasing the ion fluence leads to an increase of the saturation magnetization at 1.5 K, whereby both Ar+ and Co+ cause an increased magnetization,
respectively to 150 kA.m−1 and 190 kA.m−1, for the highest fluences used. At Co+ fluences of 5E13 ions.cm−2 the magnetoresistance (MR) shows a 2-order of magnitude increase, up to 3% (10 T) at 100 K. A similar effect also occurs for 5E12 ions.cm−2 Ar+ irradiated films, however, with a smaller MR-increase. The disordering of MAX phase films may reveal interesting spin-related trans-
port phenomena.