Abstract
Single crystals of Ba(FeMn)As, , have been grown and characterized by structural, magnetic, electrical transport, and thermopower measurements. Although growths of single crystals of Ba(FeMn)As for the full range were made, we find evidence for phase separation (associated with some form of immiscibility) starting for –0.2. Our measurements show that whereas the structural/magnetic phase transition found in pure BaFeAs at 134 K is initially suppressed by Mn substitution, superconductivity is not observed at any substitution level. Although the effect of hydrostatic pressure up to 20 kbar in the parent BaFeAs compound is to suppress the structural/magnetic transition at the approximate rate of 0.9 K/kbar, the effects of pressure and Mn substitution in the compound are not cumulative. Phase diagrams of transition temperature versus substitution concentration based on electrical transport, magnetization, and thermopower measurements have been constructed and compared to those of the Ba(FeTM)As (TM= Co and Cr) series.
12 More- Received 9 September 2011
DOI:https://doi.org/10.1103/PhysRevB.84.144528
©2011 American Physical Society