Abstract
The c-axis and in-plane alignment of 23 K Pr <sub>1.85</sub> Ce <sub>0.15</sub> CuO <sub>3.97</sub> superconducting powder were achieved with powder/epoxy cylindrical holder perpendicular and parallel to the alignment field. The temperature dependencies of basal-plane penetration depth λ <sub>ab</sub> (T) and c-axis Josephson penetration depth λ <sub>c</sub> (T) were derived using zero-field-cooled diamagnetic susceptibility χ <sub>d</sub> (T) in a low applied field (B <sub>a</sub> < H <sub>c1</sub> ) parallel or perpendicular to the aligned powder where small Pr Curie-Weiss paramagnetic susceptibility χ <sub>p</sub> (T) was subtracted. Up to 0.5T <sub>c</sub> , Δλ <sub>ab</sub> (T) = λ <sub>ab</sub> (T) - λ <sub>ab</sub> (0) as well as Josephson Δλ <sub>c</sub> (T) can be well fitted with a d-wave-like power law c <sub>2</sub> T <sup>2</sup> + c <sub>4</sub> T <sup>4</sup> , where T <sup>2</sup> -term is dominated below 0.3T <sub>c</sub> . The present result agrees with recent phase-sensitive experiment, which indicates d-wave nature for electron-doped R <sub>1.85</sub> Ce <sub>0.15</sub> CuO <sub>4-δ</sub> (R = Pr, Nd) cuprates. © 2001 Elsevier Science B.V. All rights reserved.