Superconductivity: The Century of Dreams, Discoveries and Disappointments

This book recounts the story of superconductivity -- the ability of certain materials to conduct electric current without any resistance and heat generation -- one of the most remarkable and enigmatic physical phenomena discovered in the 20th century. For decades, it defied explanation. The book opens with the historical context of its discovery in 1911, tracing the early excitement and subsequent frustrations, the relentless search for new superconducting materials, and the uncovering of their extraordinary properties.The first insights and misconceptions in the search for an understanding of the nature of superconductivity, conjectures about its quantum nature, the discovery and rapid explanation of a related phenomenon, superfluidity, and then more wandering in the dark.Forty-six years after the original discovery, the mystery was finally unraveled: the quantum mechanisms of superconductivity were understood, and the corresponding equations were formulated. One of the key barriers to practical use -- superconductors' incompatibility with noticeable magnetic fields -- was overcome. Yet, a major challenge remained: superconductivity only occurred at extremely low temperatures, close to that of liquid helium.It would take another thirty years before this limitation was broken. Seventy-five years after superconductivity was first observed in mercury at 4.15 K, researchers began synthesizing new superconductors whose critical temperatures rose dramatically -- several times over in a matter of months -- and ultimately exceeded the boiling point (77 K) of inexpensive liquid nitrogen and approaching ambient winter temperatures.The final chapters of the book focus on this modern era of superconductivity research and its real-world applications. But more than just a scientific account, the book celebrates the people behind the progress -- those whose creativity and persistence brought us high-speed magnetic levitation trains, non-invasive medical imaging, efficient energy storage and transmission, ultra-sensitive sensors, and the foundations of quantum technology.