In-situ hydrostatic pressure induced significant suppression of magnetic relaxation and enhancement of flux pinning in Fe1−xCoxSe0.5Te0.5 single crystals

We report the first study on the significant effect of in-situ hydrostatic pressure on the magnetic relaxation in Fe1−xCoxSe0.5Te0.5 single crystals. We find that vortex creep rates are significantly suppressed by pressure, and a crossover from elastic to plastic creep is observed. The pressure also induces vortex creep to move from the large bundle to the small bundle region. Our study indicates that in-situ hydrostatic pressure is very effective for not only significantly increasing the pinning energy and the critical current density, but also reducing the size of flux bundles to suppress the decrease in current density from vortex motion.