Published Paper Details:

Superconductivity, characterized by zero electrical resistance and the expulsion of magnetic fields, remains a cornerstone of condensed matter physics with transformative technological potential. This review provides a comprehensive overview of both theoretical and experimental developments in the field. We discuss foundational models, including the London, Ginzburg-Landau, Bardeen-Cooper-Schrieffer (BCS), and Eliashberg formalisms, as well as unconventional approaches such as the Resonating Valence Bond (RVB) theory, which address strong correlations and non-phonon pairing mechanisms. The review covers a broad spectrum of materials, from conventional low-temperature metals to high-temperature cuprates, iron-based superconductors, hydrogen-rich compounds under extreme pressure, and novel systems including twisted bilayer graphene, nickelates, two-dimensional materials, and topological superconductors. Key challenges for practical applications such as, cryogenic requirements, mechanical fragility, limited current-carrying capacity, fabrication difficulties, and vortex dynamics, are examined, alongside emerging strategies in scalable fabrication, vortex pinning engineering, and cryogen-free technologies. We also highlight the role of superconductors in quantum technologies, particularly superconducting qubits and topological platforms. Finally, we outline future directions, emphasizing material discovery, theoretical refinement, and engineering innovations aimed at achieving room-temperature, ambient-pressure superconductivity.