Comparative Analysis of Superconducting Properties in η-Carbide-Type Oxide Compound

This study investigates the superconducting behavior of three η-carbide-type oxides: **Zr₄Pd₂O**, **Zr₄Rh₂O**, and **Ti₄Ir₂O**. Using theoretical anisotropic energy models and experimental upper critical field data, we correlate the directional anisotropy energy $E^*$ with superconducting performance parameters such as the upper critical field $\mu_0H_{c2}(0)$, Pauli paramagnetic limit $\mu_0H_P$, transition temperature $T_c$, coherence length $\xi$, and penetration depth $\lambda$. The compound **Ti₄Ir₂O** emerges as an **excellent superconductor**, **Zr₄Pd₂O** as **moderate**, and **Zr₄Rh₂O** as the **least** performing in terms of superconducting enhancement.