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Measuring the interaction force between a high temperature superconductor and a permanent magnet

S. O. Valenzuela·G. A. Jorge·E. Rodriguez
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Abstract

Repulsive and attractive forces are both possible between a superconducting sample and a permanent magnet, and they can give place to magnetic levitation or free-suspension phenomena, respectively. We show experiments to quantify this magnetic interaction which represents a promising field regarding to short-term technological applications of high temperature superconductors. The measuring technique employs an electronic balance and a rare-earth magnet that induces a magnetic moment in a melt-textured YBa2Cu3O7 superconductor immersed in liquid nitrogen. The simple design of the experiments allows a fast and easy implementation in the advanced physics laboratory with a minimum cost. Actual levitation and suspension demonstrations can be done simultaneously as a help to interpret magnetic force measurements.

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S. O. Valenzuela, G. A. Jorge, E. Rodriguez. 1999-05-06. Measuring the interaction force between a high temperature superconductor and a permanent magnet. https://doi.org/10.1119/1.19160

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