Microstructure and Microwave Properties of YBa₂Cu₃O_7-δ Thin Film on CaNdAlO₄(001)

Abstract

High-quality YBa2Cu3O7-δ thin films have been grown on CaNdAlO4 (001) substrates by in situ laser ablation. The best transition temperature determined by AC susceptibility midpoint was 88.3 K with a critical current density of 1.0×106 A/cm2 at 77 K. The full width at half maximum of the X-ray rocking curve of the YBCO (004) peak was 0.33°. The film crystallinity was slightly worse than those grown on LaAlO3 and NdGaO3 judging from electron channeling pattern. A 2.3 GHz resonator made from a YBCO film on CaNdAlO4 exhibited a low power Q of 3,945 which is worse than films on LaAlO3 (Q∼18,000) and also lower than the expected value from loss tangent data.

Electron channeling patterns of a-axis and c-axis YBa2Cu3O7−δ thin films

“…The ECP quality for various substrates at different electron energies has been studied and will be published elsewhere. 16 The schematic illustration of the c-axis ECP is shown in Fig. 3(b); for simplicity, we illustrated only the details in the third quadrant.…”

Microstructures and electric characteristics of SrNdCoO4 ceramics with K2NiF4 structure

“…In light of the discovery of high temperature superconductivity [2] in the system La 2−x M x CuO 4 (M=Ba, Sr, Ca), it is interesting to investigate other oxides possessing the K 2 NiF 4 structure. Recently, MRAlO 4 (M=Sr, Ca; R=La, Nd, Sm and Y) crystals and ceramics with K 2 NiF 4 structure have attracted much scientific attention because of their interesting dielectric characteristics and their potential applications as substrates [3][4][5][6]. Moreover, these materials have been studied as good candidates of microwave dielectric materials in our group [7,8].…”