Name: superconductor critical temperature
Uploaded: 2025-05-22T09:05:52.000Z
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K12 Standards

Virginia  Standards of Learning

HIgh School

Physics

PH.9

PH.9.g

Superconductor

Un superconductor es un material que ofrece cero resistencia al flujo de electrones con una transferencia eficiente de energía eléctrica y sin pérdida de calor.
En 1911, Heike Kamerlingh Onnes observó que la resistencia llega a cero cuando el mercurio se enfría por debajo de 4,2 Kelvin. Esto se conoce como la temperatura crítica para el mercurio, y el fenómeno se conoce como superconductividad.
Cuando la temperatura aumenta por encima de la temperatura crítica, la resistencia cambia linealmente con ella.
Otro aspecto del comportamiento magnético de un superconductor se observa cuando un material superconductor homogéneo se coloca en un campo magnético uniforme externo.
Cuando la temperatura es mayor que la temperatura crítica, el campo dentro del material es igual al campo magnético uniforme externo. Si es más bajo que la temperatura crítica, el flujo magnético es expulsado del material y el campo dentro de él es cero. Este fenómeno se conoce como efecto Meissner.
La superconductividad de un material por debajo de la temperatura crítica puede eliminarse aplicando la magnitud mínima del campo magnético, conocida como campo magnético crítico.

<ol>
	<li>OpenStax. (2019). Física Universitaria Vol. 2. [Versión web], págs. 396 - 398. Obtenido de <a href="https://openstax.org/books/university-physics-volume-2/pages/9-6-superconductors">https://openstax.org/books/university-physics-volume-2/pages/9-6-superconductors</a></li>
</ol>

superconductor

Una sustancia que alcanza la superconductividad, un estado en el cual los campos magnéticos no pueden penetrar y no hay resistencia eléctrica, es conocida como superconductor. En 1911, Heike Kamerlingh Onnes de la Universidad de Leiden, un físico holandés, observó una relación entre la temperatura y la resistencia del elemento mercurio. La muestra de mercurio fue enfriada en helio líquido para estudiar la dependencia lineal de la resistencia con la temperatura. Se observó que, a medida que la temperatura disminuía, la resistencia disminuía. Kamerlingh Onnes continuó enfriando aún más la muestra de mercurio, y cuando la temperatura alcanzó los 4.2 K, la resistencia cayó abruptamente a cero. Esta es la temperatura crítica para el mercurio, donde la muestra de mercurio entra en una fase con resistencia cero absoluta, y este fenómeno es conocido como superconductividad. En el caso de los conductores, la resistencia no es igual a cero, pero es menor a 0.01 Ω. Existen diversos métodos para medir resistencias muy pequeñas, como el método de los cuatro puntos, pero un óhmetro no es adecuado para medir la resistencia de la superconductividad. Se han descubierto varios otros materiales que están en la fase superconductora cuando la temperatura se acerca al cero absoluto. En 1941, se descubrió que una aleación de niobio-nitruro se volvía superconductora a 16 kelvin; de manera similar, en 1953, se descubrió que el vanadio-silicio se volvía superconductor a 17.5 kelvin. Las temperaturas para la transición a la superconductividad iban aumentando lentamente. Sorprendentemente, muchos buenos conductores, como el cobre, la plata y el oro, no muestran superconductividad.

Una sustancia que alcanza la superconductividad, un estado en el que los campos magnéticos no pueden penetrar y no hay resistencia eléctrica, se conoce como ...

Education

Educación

JoVE Core

Física

Unit 1

Unidad 1

Electromagnetic Induction

Inducción electromagnética

KEY TERMS AND CONCEPTS

TÉRMINOS Y CONCEPTOS CLAVE

superconductor critical temperature

Superconductivity is the state in which a material has no electrical resistance and magnetic fields cannot penetrate it. A material that reaches this state is called a superconductor. The key idea in the transcript is the critical temperature, which is the temperature at which the change happens.

Heike Kamerlingh Onnes of Leiden University first observed this behavior in mercury in 1911. He cooled a mercury sample in liquid helium to study how resistance changed with temperature. As the temperature fell, the resistance also fell. When the temperature approached 4.2 K, the resistance suddenly dropped to zero. That temperature is the critical temperature for mercury, and the mercury sample entered a superconducting phase with absolute zero resistance.

A normal conductor is different because its resistance is not zero, even when it is very small. In the transcript, conductors are described as having resistance less than 0.01 Ω. Very small resistances can be measured with methods such as the four-point method. An ohmmeter, however, is not acceptable for testing superconductivity resistance.

Other materials have also been found in the superconducting phase near absolute zero. In 1941, an alloy of niobium-nitride became superconducting at 16 kelvin. In 1953, vanadium-silicon became superconductive at 17.5 kelvin. These discoveries showed that transition temperatures were slowly increasing. Even so, many good conductors such as copper, silver, and gold do not show superconductivity.

Superconductor Critical Temperature

induction

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Superconductivity is the state in which a material has no electrical resistance and magnetic fields cannot penetrate it. A material that reaches this state is called a superconductor. The key idea in the transcript is the critical temperature, which is the temperature at which the change happens. Heike Kamerlingh Onnes of Leiden University first observed this behavior in mercury in 1911. He cooled a mercury sample in liquid helium to study how resistance changed with temperature. As the...

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lenz's law

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induced electric fields: applications

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electromagnetic fields

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key terms and concepts

Learn how superconductivity appears at a critical temperature, why mercury became a classic example, and how other materials also show zero resistance.

Superconductor Critical Temperature | JoVE K12

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Superconductor Critical Temperature

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