THE EFFECT OF OXYGEN CONTENT ON MAGNETIC LEVITATION IN Y-123 CUPRATE SUPERCONDUCTORS

YBa2Cu3O7-δ (YBCO, also known as Y-123) is one of the most important high-temperature cuprate superconductors because it can become superconducting above the boiling point of liquid nitrogen. Its ability to levitate a permanent magnet, however, is not determined only by low temperature; it is strongly controlled by oxygen stoichiometry. Oxygen atoms occupy chain sites in the YBCO structure, regulate hole concentration in the CuO2 planes, stabilize the orthorhombic superconducting phase, and influence the critical temperature, critical current density, and flux-pinning strength. This article explains how oxygen-rich YBCO produces strong and stable magnetic levitation through the combined action of the Meissner effect and vortex pinning, while oxygen-deficient YBCO progressively loses superconducting and levitation performance. The discussion emphasizes the structural role of oxygen, the link between oxygen content and superconducting parameters, the physical interpretation of the levitation demonstration, and the practical importance of oxygen control in magnetic bearings, flywheel energy storage, and maglev systems.