Magnetostriction-induced in situ strain control of superconductivity in FeSe0.5Te0.5.

In the superconductor of FeSe0.5Te0.5, the superconductivity is highly sensitive to variations of microstructure. Therefore, a fine manipulation of the microstructures will be crucial not only for a better understanding of the superconductivity but also for potential applications. Here, we demonstrate an approach to control the superconductivity in-situ by using a magnetostrictive substrate ZnCr2Se4 as the strain generator. By mounting an FeSe0.5Te0.5 single crystal onto a magnetostrictive substrate, we show that the magnetoresistance of FeSe0.5Te0.5 is directly coupled to the magnetostriction of ZnCr2Se4. The strain is fine-tuned in-situ by an external magnetic field, leading to the superconductivity of FeSe0.5Te0.5 correspondingly favored by compressive strain while suppressed by tensile strain. [ABSTRACT FROM AUTHOR]