Thermodynamic assessment of the Co-Mg binary system

No thermodynamic description was performed for the Co-Mg binary system according to literature review. Consequently, this binary system has been investigated by means of CALPHAD (CALculation of PHAse Diagrams) approach in the present work. The experimental phase diagram and thermodynamic data available in the literature were critically assessed. Based on the reliable literature data, a new set of self-consistent thermodynamic parameters for the Co-Mg system is obtained. The calculated results agree well with the experimental data from the literature, indicating the reasonability of the present thermodynamic optimization.

Doping-dependent competition between superconductivity and polycrystalline charge density waves

From systematic analysis of the high pulsed magnetic field resistance data of La_{2-x}2−xSr_xxCuO_{4}4 thin films, we extract an experimental phase diagram for several doping values ranging from the very underdoped to the very overdoped regimes. Our analysis highlights a competition between charge density waves and superconductivity which is ubiquitous between x=0.08x=0.08 and x=0.19x=0.19 and produces the previously observed double step transition. When suppressed by a strong magnetic field, superconductivity is resilient for two specific doping ranges centered around respectively x\approx 0.09x≈0.09 and x\approx 0.19x≈0.19 and the characteristic temperature for the onset of the competing charge density wave phase is found to vanish above x = 0.19x=0.19. At x=1/8x=1/8 the two phases are found to coexist exactly at zero magnetic field.