Meissner effect

Meiss·ner effect

M5213750 (mīs′nər)n. The effect whereby magnetic fields are excluded from a superconductor's interior if the superconductor is below a critical temperature, since introducing a magnetic field immediately creates electric currents in the superconductor that cancel the magnetic field. The Meissner effect is responsible for the diamagnetic properties of superconductors.

[After Fritz Walther Meissner (1882-1974), German physicist who discovered it in collaboration with Robert Ochsenfeld (1901-1993), German physicist.]

Meissner effect

(ˈmaɪsnə) n (General Physics) physics the phenomenon in which magnetic flux is excluded from a substance when it is in a superconducting state, except for a thin layer at the surface[C20: named after Fritz Walther Meissner (1882–1974), German physicist]

Meissner Effect

Meissner effect

The expulsion of magnetic flux from the interior of a superconducting metal when it is cooled in a magnetic field to below the critical temperature, near absolute zero, at which the transition to superconductivity takes place. It was discovered by Walther Meissner in 1933, when he measured the magnetic field surrounding two adjacent long cylindrical single crystals of tin and observed that at -452.97°F (3.72 K) the Earth's magnetic field was expelled from their interior. This indicated that at the onset of superconductivity they became perfect diamagnets. This discovery showed that the transition to superconductivity is reversible, and that the laws of thermodynamics apply to it. The Meissner effect forms one of the cornerstones in the understanding of superconductivity, and its discovery led F. London and H. London to develop their phenomenological electrodynamics of superconductivity. See Diamagnetism, Thermodynamic principles

The magnetic field is actually not completely expelled, but penetrates a very thin surface layer where currents flow, screening the interior from the magnetic field.

The Meissner effect is subject to limitations. Full diamagnetism is not observed in polycrystalline samples, and the effect is not observed in impure samples or samples with certain geometrics, such as a round flat disk, with the magnetic field parallel to the axis of rotation. See Superconductivity

Meissner Effect

the complete expulsion of a magnetic field from a metal conductor when it becomes superconductive (when the intensity of the applied magnetic field is less than the critical value H_c). The Meissner effect was first observed in 1933 by the German physicists W. Meissner and R. Oxenfeld. Partial “freezing” of the magnetic field in the superconductor—that is, incompleteness of the Meissner effect—is observed in insufficiently pure metals and especially in alloys.

Meissner effect

[′mīs·nər i‚fekt] (solid-state physics) The expulsion of magnetic flux from the interior of a piece of superconducting material as the material undergoes the transition to the superconducting phase. Also known as flux jumping; Meissner-Ochsenfeld effect.

单词	meissner effect
释义	Meissner effect Meiss·ner effect M5213750 (mīs′nər)n. The effect whereby magnetic fields are excluded from a superconductor's interior if the superconductor is below a critical temperature, since introducing a magnetic field immediately creates electric currents in the superconductor that cancel the magnetic field. The Meissner effect is responsible for the diamagnetic properties of superconductors. [After Fritz Walther Meissner (1882-1974), German physicist who discovered it in collaboration with Robert Ochsenfeld (1901-1993), German physicist.] Meissner effect (ˈmaɪsnə) n (General Physics) physics the phenomenon in which magnetic flux is excluded from a substance when it is in a superconducting state, except for a thin layer at the surface[C20: named after Fritz Walther Meissner (1882–1974), German physicist] Meissner Effect Meissner effect The expulsion of magnetic flux from the interior of a superconducting metal when it is cooled in a magnetic field to below the critical temperature, near absolute zero, at which the transition to superconductivity takes place. It was discovered by Walther Meissner in 1933, when he measured the magnetic field surrounding two adjacent long cylindrical single crystals of tin and observed that at -452.97°F (3.72 K) the Earth's magnetic field was expelled from their interior. This indicated that at the onset of superconductivity they became perfect diamagnets. This discovery showed that the transition to superconductivity is reversible, and that the laws of thermodynamics apply to it. The Meissner effect forms one of the cornerstones in the understanding of superconductivity, and its discovery led F. London and H. London to develop their phenomenological electrodynamics of superconductivity. See Diamagnetism, Thermodynamic principles The magnetic field is actually not completely expelled, but penetrates a very thin surface layer where currents flow, screening the interior from the magnetic field. The Meissner effect is subject to limitations. Full diamagnetism is not observed in polycrystalline samples, and the effect is not observed in impure samples or samples with certain geometrics, such as a round flat disk, with the magnetic field parallel to the axis of rotation. See Superconductivity Meissner Effect the complete expulsion of a magnetic field from a metal conductor when it becomes superconductive (when the intensity of the applied magnetic field is less than the critical value H_c). The Meissner effect was first observed in 1933 by the German physicists W. Meissner and R. Oxenfeld. Partial “freezing” of the magnetic field in the superconductor—that is, incompleteness of the Meissner effect—is observed in insufficiently pure metals and especially in alloys. Meissner effect [′mīs·nər i‚fekt] (solid-state physics) The expulsion of magnetic flux from the interior of a piece of superconducting material as the material undergoes the transition to the superconducting phase. Also known as flux jumping; Meissner-Ochsenfeld effect.
随便看	optional form optional halt instruction optional hyphen optional inter partes reexamination procedure act of 1999 optionality optionally optional modification optional network specific digit optional payment bond optional points optional port of loading optional practical training optional procedure optional procedure indicator optional product optional residence telephone service optional retirement program optional state supplementation optional stop instruction optional surgery option approach option backdating option based portfolio insurance option by ibm option chain