Dynamics of trapped magnetic flux in superconducting FeTe₀.₆₅Se₀.₃₅

Abstract

The magnetic moment in the superconducting and normal state of a crystalline FeTe₀.₆₅Se₀.₃₅ superconductor, grown by the Bridgman's method with relatively high growth rate, was measured. The temperature and magnetic field dependences of magnetization and its relaxation time were determined. Studied crystal, being non-uniform due to high growth rate of 5 mm/h, exhibits smaller width of superconducting transition in comparison with an ideal crystal grown with velocity of 1 mm/h, and the difference in magnetic properties of crystals grown with various growth rate, related to their microstructure, is discussed.