Meissner effect - Revision history

Dwiens3: /* History */

2017-11-30T00:41:52Z

History

← Older revision		Revision as of 20:41, 29 November 2017
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	The most important discovery leading up to the discovery of the Meissner effect was the discovery of superconductivity in 1911 by Heike Onnes. He discovered superconductivity by observing the resistance of mercury as he cooled it. When cooled mercury to 4.2 K, he measured the resistance to be 0. Thus, mercury was conducting electricity perfectly and was a "super" conductor.		The most important discovery leading up to the discovery of the Meissner effect was the discovery of superconductivity in 1911 by Heike Onnes. He discovered superconductivity by observing the resistance of mercury as he cooled it. When cooled mercury to 4.2 K, he measured the resistance to be 0. Thus, mercury was conducting electricity perfectly and was a "super" conductor.

	The knowledge of superconductors was expanded upon in 1933 when two German physicists, Robert Ochsenfeld and Walther Meissner discovered the Meissner effect. They were able to do discover the electric field created in the superconductor in the presence of another electric field, not by measuring the electric field directly, but by measuring the associated flux through the ~~super conductor~~.		The knowledge of superconductors was expanded upon in 1933 when two German physicists, Robert Ochsenfeld and Walther Meissner discovered the Meissner effect. They were able to do discover the electric field created in the superconductor in the presence of another electric field, not by measuring the electric field directly, but by measuring the associated flux through the superconductor.

	The theory of the Meissner effect led to the phenomenological theory of superconductivity by Frits London and Heinz London in 1935. This theory explained resistance less transport and the Meissner effect, and allowed the first theoretical predictions for superconductivity to be made as seen below.		The theory of the Meissner effect led to the phenomenological theory of superconductivity by Frits London and Heinz London in 1935. This theory explained resistance less transport and the Meissner effect, and allowed the first theoretical predictions for superconductivity to be made as seen below.

Dwiens3: /* History */

2017-11-30T00:40:45Z

History

← Older revision		Revision as of 20:40, 29 November 2017
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	==History==		==History==
	The most important discovery leading up to the discovery of the Meissner effect was the discovery of superconductivity in 1911 by Heike Onnes. He discovered superconductivity by observing the resistance of mercury as he cooled it. When cooled mercury to 4.2 K, he measured the resistance to be 0. Thus, mercury was conducting electricity perfectly and was a "super" conductor.		The most important discovery leading up to the discovery of the Meissner effect was the discovery of superconductivity in 1911 by Heike Onnes. He discovered superconductivity by observing the resistance of mercury as he cooled it. When cooled mercury to 4.2 K, he measured the resistance to be 0. Thus, mercury was conducting electricity perfectly and was a "super" conductor.

			The knowledge of superconductors was expanded upon in 1933 when two German physicists, Robert Ochsenfeld and Walther Meissner discovered the Meissner effect. They were able to do discover the electric field created in the superconductor in the presence of another electric field, not by measuring the electric field directly, but by measuring the associated flux through the super conductor.

	The theory of the Meissner effect led to the phenomenological theory of superconductivity by Frits London and Heinz London in 1935. This theory explained resistance less transport and the Meissner effect, and allowed the first theoretical predictions for superconductivity to be made as seen below.		The theory of the Meissner effect led to the phenomenological theory of superconductivity by Frits London and Heinz London in 1935. This theory explained resistance less transport and the Meissner effect, and allowed the first theoretical predictions for superconductivity to be made as seen below.

Dwiens3: /* A Computational Model */

2017-11-29T22:48:04Z

A Computational Model

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	===A Computational Model===		===A Computational Model===
	[[File:MeissnerEffect.jpg]]		[[File:Users/DavidWiens/Desktop/MeissnerEffect.jpg]]

	==Examples==		==Examples==

Dwiens3: /* A Computational Model */

2017-11-29T22:42:44Z

A Computational Model

← Older revision		Revision as of 18:42, 29 November 2017
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	===A Computational Model===		===A Computational Model===
			[[File:MeissnerEffect.jpg]]

	==Examples==		==Examples==

Dwiens3: /* History */

2017-11-29T21:19:16Z

History

← Older revision		Revision as of 17:19, 29 November 2017
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	==History==		==History==
			The most important discovery leading up to the discovery of the Meissner effect was the discovery of superconductivity in 1911 by Heike Onnes. He discovered superconductivity by observing the resistance of mercury as he cooled it. When cooled mercury to 4.2 K, he measured the resistance to be 0. Thus, mercury was conducting electricity perfectly and was a "super" conductor.

	The theory of the Meissner effect led to the phenomenological theory of superconductivity by Frits London and Heinz London in 1935. This theory explained resistance less transport and the Meissner effect, and allowed the first theoretical predictions for superconductivity to be made as seen below.		The theory of the Meissner effect led to the phenomenological theory of superconductivity by Frits London and Heinz London in 1935. This theory explained resistance less transport and the Meissner effect, and allowed the first theoretical predictions for superconductivity to be made as seen below.

Dwiens3: /* Type I and Type II Superconductors */

2017-11-29T21:04:41Z

Type I and Type II Superconductors

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	There are two categories of superconductors that relate to the Meissner effect: Type I and Type II. Type I superconductors consist of pure metals that act as superconductors, while Type II superconductors are alloys that act as superconductors.		There are two categories of superconductors that relate to the Meissner effect: Type I and Type II. Type I superconductors consist of pure metals that act as superconductors, while Type II superconductors are alloys that act as superconductors.

	Type I superconductors exclude magnetic fields completely due to the Meissner effect when they are cooled to a certain temperature and when the magnetic field is not extremely high. Type I superconductors are usually metals and only become superconductors at very low degrees Kelvin. The temperature at which a metal becomes a superconductor is referred to as its Critical Temperature or Tc. One example of a Type I superconductor is Mercury, which has a critical point of 4.2 K. The other important characteristic of a Type I superconductor is the magnitude of the magnetic field at which the metal no longer can exclude the magnetic field completely. This magnetic field magnitude is referred to as the critical magnetic field or Hc. Mercury has a critical magnetic field of .04 T.		'''Type I superconductors''' exclude magnetic fields completely due to the Meissner effect when they are cooled to a certain temperature and when the magnetic field is not extremely high. Type I superconductors are usually metals and only become superconductors at very low degrees Kelvin. The temperature at which a metal becomes a superconductor is referred to as its Critical Temperature or Tc. One example of a Type I superconductor is Mercury, which has a critical point of 4.2 K. The other important characteristic of a Type I superconductor is the magnitude of the magnetic field at which the metal no longer can exclude the magnetic field completely. This magnetic field magnitude is referred to as the critical magnetic field or Hc. Mercury has a critical magnetic field of .04 T.

	Type II superconductors, on the other hand, are typically a mixture of normal and superconducting regions. Type II superconductors do not obey the Meissner effect perfectly. Instead, they only partially exclude the magnetic and slowly lose their superconductivity. The magnitude of the magnetic field at which a type II superconductor begins to partially lose its superconductivity is referred to as Hc1. The magnitude of the magnetic field at which a type II superconductor completely loses its superconductivity is referred to as Hc2.		'''Type II superconductors''', on the other hand, are typically a mixture of normal and superconducting regions. Type II superconductors do not obey the Meissner effect perfectly. Instead, they only partially exclude the magnetic and slowly lose their superconductivity. The magnitude of the magnetic field at which a type II superconductor begins to partially lose its superconductivity is referred to as the lower critical magnetic field or Hc1. The magnitude of the magnetic field at which a type II superconductor completely loses its superconductivity is referred to as the upper critical magnetic field or Hc2.

	===A Mathematical Model===		===A Mathematical Model===

Dwiens3: /* Type I and Type II Superconductors */

2017-11-29T21:00:21Z

Type I and Type II Superconductors

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	Type I superconductors exclude magnetic fields completely due to the Meissner effect when they are cooled to a certain temperature and when the magnetic field is not extremely high. Type I superconductors are usually metals and only become superconductors at very low degrees Kelvin. The temperature at which a metal becomes a superconductor is referred to as its Critical Temperature or Tc. One example of a Type I superconductor is Mercury, which has a critical point of 4.2 K. The other important characteristic of a Type I superconductor is the magnitude of the magnetic field at which the metal no longer can exclude the magnetic field completely. This magnetic field magnitude is referred to as the critical magnetic field or Hc. Mercury has a critical magnetic field of .04 T.		Type I superconductors exclude magnetic fields completely due to the Meissner effect when they are cooled to a certain temperature and when the magnetic field is not extremely high. Type I superconductors are usually metals and only become superconductors at very low degrees Kelvin. The temperature at which a metal becomes a superconductor is referred to as its Critical Temperature or Tc. One example of a Type I superconductor is Mercury, which has a critical point of 4.2 K. The other important characteristic of a Type I superconductor is the magnitude of the magnetic field at which the metal no longer can exclude the magnetic field completely. This magnetic field magnitude is referred to as the critical magnetic field or Hc. Mercury has a critical magnetic field of .04 T.

	Type II superconductors, on the other hand, are typically a mixture of normal and superconducting regions. ~~This mixture causes~~ Type II superconductors to not ~~completely~~ exclude magnetic ~~fields,~~ and ~~instead constrain~~ the ~~fields~~ to ~~filaments within~~ the ~~material, creating what~~ is ~~sometimes~~ referred to as ~~the vortex state~~.		Type II superconductors, on the other hand, are typically a mixture of normal and superconducting regions. Type II superconductors do not obey the Meissner effect perfectly. Instead, they only partially exclude the magnetic and slowly lose their superconductivity. The magnitude of the magnetic field at which a type II superconductor begins to partially lose its superconductivity is referred to as Hc1. The magnitude of the magnetic field at which a type II superconductor completely loses its superconductivity is referred to as Hc2.

	===A Mathematical Model===		===A Mathematical Model===

Dwiens3: /* Type I and Type II Superconductors */

2017-11-29T20:52:22Z

Type I and Type II Superconductors

← Older revision		Revision as of 16:52, 29 November 2017
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	There are two categories of superconductors that relate to the Meissner effect: Type I and Type II. Type I superconductors consist of pure metals that act as superconductors, while Type II superconductors are alloys that act as superconductors.		There are two categories of superconductors that relate to the Meissner effect: Type I and Type II. Type I superconductors consist of pure metals that act as superconductors, while Type II superconductors are alloys that act as superconductors.

	Type I superconductors exclude magnetic fields completely due to the Meissner effect when they are cooled to a certain temperature and when the magnetic field is not extremely high. Type I superconductors are usually metals and only become superconductors at very low degrees Kelvin. The temperature at which a metal becomes a superconductor is referred to as its Critical Temperature or Tc. One example of a Type I superconductor is Mercury, which has a critical point of 4.2 K. The other important characteristic of a Type I superconductor is the magnitude of the magnetic field at which the metal no longer can exclude the magnetic field completely. This magnetic field magnitude is referred to as		Type I superconductors exclude magnetic fields completely due to the Meissner effect when they are cooled to a certain temperature and when the magnetic field is not extremely high. Type I superconductors are usually metals and only become superconductors at very low degrees Kelvin. The temperature at which a metal becomes a superconductor is referred to as its Critical Temperature or Tc. One example of a Type I superconductor is Mercury, which has a critical point of 4.2 K. The other important characteristic of a Type I superconductor is the magnitude of the magnetic field at which the metal no longer can exclude the magnetic field completely. This magnetic field magnitude is referred to as the critical magnetic field or Hc. Mercury has a critical magnetic field of .04 T.

	Type II superconductors, on the other hand, are typically a mixture of normal and superconducting regions. This mixture causes Type II superconductors to not completely exclude magnetic fields, and instead constrain the fields to filaments within the material, creating what is sometimes referred to as the vortex state.		Type II superconductors, on the other hand, are typically a mixture of normal and superconducting regions. This mixture causes Type II superconductors to not completely exclude magnetic fields, and instead constrain the fields to filaments within the material, creating what is sometimes referred to as the vortex state.

Dwiens3: /* What is the Meissner Effect */

2017-11-29T20:44:08Z

What is the Meissner Effect

← Older revision		Revision as of 16:44, 29 November 2017
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	==What is the Meissner Effect==		==What is the Meissner Effect==

	The Meissner effect is the expulsion of a magnetic field from a superconductor during its transition to the superconducting state. Below the transition temperature, superconductors cancel nearly all interior magnetic fields actively. The effect that occurs, leading to a zero net magnetic effect in the material, can be attributed to diamagnetism.		The Meissner effect is the expulsion of a magnetic field from a superconductor during its transition to the superconducting state. Below the transition temperature, superconductors cancel nearly all interior magnetic fields actively. The effect that occurs, leading to a zero net magnetic effect in the material, can be attributed to diamagnetism.

			The Meissner effect is most often demonstrated by a magnate suspended above a superconductor. Because of the Meissner effect, a magnetic field is created in the superconductor that exactly mirrors the magnetic field of the magnet. Thus, the magnetic force on the magnet is upwards, in the opposite direction of gravity. When the magnet reaches a distance far enough above the superconductor, the magnetic force from the superconductor is equal to and opposite of the force of gravity. Thus, the net force is zero so the magnet remains suspended above the superconductor at a constant position, appearing to levitate.

	[[File:Meissner effect1.png\|200px\|thumb\|right\|alt text]]		[[File:Meissner effect1.png\|200px\|thumb\|right\|alt text]]

Dwiens3: /* Type I and Type II Superconductors */

2017-11-29T03:35:54Z

Type I and Type II Superconductors

← Older revision		Revision as of 23:35, 28 November 2017
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	===Type I and Type II Superconductors===		===Type I and Type II Superconductors===
	There are two categories of superconductors that relate to the Meissner effect: Type I and Type II. Type I superconductors consist of pure metals that act as superconductors, while Type II superconductors are alloys that act as superconductors. Type I superconductors exclude magnetic fields completely due to the Meissner effect. Type II superconductors, on the other hand, are typically a mixture of normal and superconducting regions. This mixture causes Type II superconductors to not completely exclude magnetic fields, and instead constrain the fields to filaments within the material, creating what is sometimes referred to as the vortex state.		There are two categories of superconductors that relate to the Meissner effect: Type I and Type II. Type I superconductors consist of pure metals that act as superconductors, while Type II superconductors are alloys that act as superconductors.

			Type I superconductors exclude magnetic fields completely due to the Meissner effect when they are cooled to a certain temperature and when the magnetic field is not extremely high. Type I superconductors are usually metals and only become superconductors at very low degrees Kelvin. The temperature at which a metal becomes a superconductor is referred to as its Critical Temperature or Tc. One example of a Type I superconductor is Mercury, which has a critical point of 4.2 K. The other important characteristic of a Type I superconductor is the magnitude of the magnetic field at which the metal no longer can exclude the magnetic field completely. This magnetic field magnitude is referred to as

			Type II superconductors, on the other hand, are typically a mixture of normal and superconducting regions. This mixture causes Type II superconductors to not completely exclude magnetic fields, and instead constrain the fields to filaments within the material, creating what is sometimes referred to as the vortex state.

	===A Mathematical Model===		===A Mathematical Model===