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The phase stability of Mo n +1GaC n has been investigated using ab-initio calculations. The results indicate stability for the Mo2GaC phase only, with a formation enthalpy of -0.4 meV per atom. Subsequent thin film synthesis of Mo2GaC was performed through magnetron sputtering from elemental targets onto Al2O3 [0001], 6H-SiC [0001] and MgO [111] substrates within the temperature range of 500 °C and 750 °C. High structural quality films were obtained for synthesis on MgO [111] substrates at 590 ºC. Evaluation of transport properties showed a superconducting behavior with a critical temperature of approximately 7 K, reducing upon the application of an external magnetic field. The results point towards the first superconducting MAX phase in thin film form. (© 2015 WILEY-VCH Verlag GmbH &Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

(Cr1- xMn x)2AlC MAX phase thin films were synthesized by cathodic arc deposition. Scanning transmission electron microscopy including local energy dispersive X-ray spectroscopy analysis of the as-deposited films reveals a Mn incorporation of as much as 10 at% in the structure, corresponding to x = 0.2. Magnetic properties were characterized with vibrating sample magnetometry, revealing a magnetic response up to at least room temperature. We thus verify previous theoretical predictions of an antiferromagnetic or ferromagnetic ground state for Cr2AlC upon alloying with Mn. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Ab-initio calculations have been used to investigate the phase stability and magnetic state of Cr n+ 1GaC n MAX phase. Cr2GaC ( n = 1) was predicted to be stable, with a ground state corresponding to an antiferromagnetic spin configuration. Thin-film synthesis by magnetron sputtering from elemental targets, including liquid Ga, shows the formation of Cr2GaC, previously only attained from bulk synthesis methods. The films were deposited at 650 °C on MgO(111) substrates. X-ray diffraction and high-resolution transmission electron microscopy show epitaxial growth of (000ℓ) MAX phase. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]