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magnetic field, H , was applied in the maximum Lorentz force configuration ( H perpendicular to J ) at an angle of Θ measured from the c -axis. The same configuration was employed for the angular-and field-dependent resistance measurements near T$_{c}$ to evaluate the upper critical field, H$_{c2}$ . 

The crystalline quality and phase purity of the thin film was examined prior to detailed transport measure- ments by θ/ 2 θ - scans, 103 φ - scans, and ω - scans of the 004 diffraction peak. It is apparent from fig. 1 (a) that only 00 l peaks of the Co-containing Ba-122 thin film together with the 200 reflection of Fe were observed. The full width at half maximum (FWHM), Δ ω , of the 004 rocking curve was 0.66 ◦ , as exhibited in fig. 1 (b). 

Furthermore, no additional peaks in the φ -scans of the 103 reflection were observed outside of a sharp, strong peak at every 90 ◦ , as shown in fig. 1 (c). The average FWHM, Δ φ , of the peaks was 1.07 ◦ . A further inves- tigation on the crystalline quality of the film has been performed by transimission electron microscopy, TEM. Shown in figs. 2 (a) and (b) are the cross-sectional TEM images together with its selected area of the electron diffraction (SAED) pattern (c), taken in a C$_{s}$-corrected 300 kV, FEI Titan. Fig. 2 (a), an overview micrograph representative of the entire 10 µ m long TEM lamella sur- veyed, reveals neither appreciable defects nor any grain boudaries. It is further apparent from figs. 2 (c) and 1 (c) that the film grows highly epitaxially with the rela- tion (001)[100]Ba-122 ‖ (001)[100]LSAT without any mis- oriented grains, which was also confirmed from the overall TEM image and pole figure measurements. From these results, we conclude that the Co-containing Ba-122 thin film is clean and of excellent crystalline quality without grain boundaries. 

The high-resolution TEM image at the interface be- tween the film and substrate reveals a thin epitaxial Fe layer of ≈ 2 nm (fig. 2 (b)). While Fe was not de- tected in the PLD target material by powder X-ray diffraction, the 200 reflection of Fe is commonly ob- served in thin films rather than high-intensity peaks such as 110 or 210, as shown in fig. 1 (a). 5,8,10 These results suggest that Fe is textured and a by-product formed during the deposition. From the above results, the epitaxial relation of the resulting film is (001)[100]Ba- 122 ‖ (001)[110]Fe ‖ (001)[100]LSAT, which was also con- firmed by φ -scans. Here, the lattice constant a of Fe (0.286 nm) multiplied by √$_{2 is close to those of LSAT}$ (0.387 nm) and BaFe$_{1}$$_{.}$$_{8}$Co$_{0}$$_{.}$$_{2}$As$_{2}$ (0.396 nm). 

Transport J$_{c}$ of the resulting thin film, which shows a T$_{c}$$_{,}$$_{90}$ of 22.3 K with a transition width, Δ T$_{c}$ , of 1.8 K (Δ T$_{c}$ = T$_{c}$$_{,}$$_{90}$ - T$_{c}$$_{,}$$_{10}$ , where T$_{c}$$_{,}$$_{90}$ and T$_{c}$$_{,}$$_{10}$ are defined as 90% and 10% of the normal resistivity at 25 K), as a function of magnetic field at different temperatures has been evaluated. The magnetic field was applied paral- lel and perpendicular to the film c -axis. J$_{c}$ values for H ‖ c are always lower than for H ⊥ c , indicating that the flux pinning is anisotropic. Further investigation of the anisotropy of flux pinning has been done by measuring J$_{c}$ as a function of angle, Θ, under different magnetic fields and temperatures. Shown in fig. 3 (a) is J$_{c}$ (Θ) under dif- ferent magnetic fields at 4.2 K. J$_{c}$ (Θ) always has a broad maximum positioned at Θ=90 ◦ ( H ⊥ c ), and this peak becomes more prominent with increasing magnetic field. These features are typically observed in layered supercon- ductors like Y-123 due to intrinsic pinning arising from correlated ab -planes and a modulation of the supercon- ducting order parameter. 16 Here we emphasize that no J$_{c}$ peaks at Θ=180 ◦ ( H ‖ c ) were observed in the whole range of temperatures as well as magnetic fields, which is consistent with the TEM results (i.e. no c -axis correlated defects were observed, as shown in fig 2 (a).). However, S. Lee et al. 10 have observed c -axis correlated defects on 

