Effects of Tilted Columnar Defects on $J_{\mathrm{c}}$ Behavior in (Ba,K)Fe$_{\mathrm{2}}$As$_{\mathrm{2}}$

Iron-based superconductors have very promising characteristics to be used for practical applications at high fields. We have already demonstrated a remarkable enhancement of $J_{\mathrm{c}}$ in (Ba,K)Fe$_{\mathrm{2}}$As$_{\mathrm{2}}$ by irradiating swift particles [1,2]. In order to further enhance $J_{\mathrm{c}}$, we introduced columnar defects at an angle from the $c$-axis. We found a novel non-monotonic field dependence of $J_{\mathrm{c}}$ as well as its enhancement in such samples at relatively high temperatures. Origins of these anomalous $J_{\mathrm{c\thinspace }}$behavior and the degree of $J_{\mathrm{c}}$ enhancement with the tilted columnar defects will be discussed. [1] T. Taen \textit{et al}., Supercond. Sci. Technol. \textbf{28}, 085003 (2015). [2] F. Ohtake \textit{et al}., Physica C\textbf{518}, 47 (2015).