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arXiv · 1207.5992

Magnetic levitation on a type-I superconductor as a practical demonstration experiment for students

M. R. Osorio·D. E. Lahera·H. Suderow
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Abstract

We describe and discuss an experimental set-up which allows undergraduate and graduate students to view and study magnetic levitation on a type-I superconductor. The demonstration can be repeated many times using one readily available 25 liter liquid helium dewar. We study the equilibrium position of a magnet that levitates over a lead bowl immersed in a liquid hand-held helium cryostat. We combine the measurement of the position of the magnet with simple analytical calculations. This provides a vivid visualization of magnetic levitation from the balance between pure flux expulsion and gravitation. The experiment contrasts and illustrates the case of magnetic levitation with high temperature type-II superconductors using liquid nitrogen, where levitation results from partial flux expulsion and vortex physics.

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M. R. Osorio, D. E. Lahera, H. Suderow. 2012-07-25. Magnetic levitation on a type-I superconductor as a practical demonstration experiment for students. https://doi.org/10.1088/0143-0807%2F33%2F5%2F1383

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