Why Do Superconductors Expel Magnetic Fields? Understanding the Meissner Effect
After becoming interested in superconductors, I noticed something familiar while watching Avatar: Unobtanium, the fictional material that appears in the movie. Seeing it suspended in the air made me wonder: “Could this be something like a superconductor?” (AI-generated image) Of course, Unobtanium is fictional. But that scene made me even more curious about superconductivity. As I began looking into how real superconductors interact with magnetic fields, I came across one of their most fascinating properties: the Meissner effect. So what exactly is the Meissner effect, and why is it so important to understanding superconductivity? The Meissner Effect: Expelling Magnetic Fields In my previous article, I explored how superconductivity was discovered in 1911, when the electrical resistance of mercury was found to disappear at extremely low temperatures. Zero electrical resistance is probably the best-known property of a superconductor. [2] But it is not the whole story. Superconductors al...