The role of Fe deficiency in FeySe0.5Te0.5 samples prepared by a melting process

Fe content plays a primary role in the structural, magnetic and transport properties of Fe(Se,Te) compounds. In this work we investigate some of these properties in ipo-stoichiometric FeySe0.5Te0.5 samples (y ? 1.00) prepared by a novel synthesis technique, involving a melting process. These samples are characterized by a pore-free microstructure with large and well interconnected grains. The composition Fe0.99Se0.5Te0.5 exhibits the best properties with an optimal critical temperature, sharp resistive and magnetic transitions, large hysteresis loops and high value of critical current density at zero field and 5 K.