Effects of irradiation-particle energy on critical current density in Co-doped BaFeAs

Taen, Toshihiro*; Yagyuda, Hidenori*; Nakajima, Yasuyuki*; Tamegai, Tsuyoshi*; Okayasu, Satoru; Kitamura, Hisashi*; Murakami, Takeshi*; Laviano, F.*; Ghigo, G.*

Physica C, 484, p.62 - 65, 2013/01

https://doi.org/10.1016/j.physc.2012.02.040

We report effects of particle energy on physical properties of Co-doped BaFeAs in the case of Xe and Au irradiations. The irradiation-induced suppression of is found to be related with several factors, such as defect structures and the thickness of the crystal. Heavy-ion irradiation induces enhancement of critical current density , and a weak dip in the hysteresis loop. The fish-tail effect is completely suppressed by a modest density of defects. The enhancement of is closely related to the defect structure. Namely, splayed structure in columnar defects, inevitably introduced at lower energies, results in a strong enhancement of by forced entanglement of vortices.