Video Experimental Relacionado
Updated: May 6, 2026
08:45
Fabrication of Spatially Confined Complex Oxides
Published on: July 1, 2013
9.1K
La competencia entre el pseudogap y la superconductividad en los óxidos de cobre de alto T (c)
Takeshi Kondo1, Rustem Khasanov, Tsunehiro Takeuchi
1Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA. kondo@ameslab.gov
Nature
|January 17, 2009
Resumen
En los superconductores de alta temperatura, una pseudobrecha compite con la superconductividad. Este estudio muestra que el pseudogap reduce el peso espectral disponible para el emparejamiento de electrones, lo que dificulta la superconductividad.
Área de la Ciencia:
- Física de la materia condensada Física de la materia condensada
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- Los superconductores clásicos exhiben emparejamiento simultáneo de electrones y coherencia por debajo de una temperatura crítica (T (c)).
- Los superconductores de óxido de cobre de alta T (c) muestran una pseudobrecha por encima de T (c), cuya relación con la superconductividad sigue siendo una pregunta clave de investigación.
- Distinguir las pseudo brechas de las brechas superconductoras es un desafío debido a sus características espectrales similares.
Objetivo del estudio:
- Investigar la competencia entre el pseudogap y la superconductividad en materiales de alta T (c).
- Determinar si el pseudogap impide la superconductividad mediante el análisis de las correlaciones de peso espectral.
Principales métodos:
- Se utilizó la espectroscopia de fotoemisión con resolución de ángulo (ARPES) para estudiar las características espectrales.
- Se analizaron dos pesos espectrales clave: el pico coherente superconductor y el peso espectral de baja energía asociado con el pseudogap.
- Examinó estas correlaciones a través de diferentes momentos y niveles de dopaje.
Principales resultados:
- Se observó un comportamiento no monótono en el peso del pico coherente superconductor, disminuyendo en la región antinodal.
- Demostró una correlación directa entre la pérdida de peso espectral de baja energía (pseudoabertura de brecha) y la disminución del peso espectral superconductor.
- Identificó un estado electrónico competidor responsable de las características del pseudogap.
Conclusiones:
- El pseudogap compite activamente con la superconductividad en materiales de alta T (c).
- Esta competencia se produce por el agotamiento del peso espectral esencial para el emparejamiento de electrones.
- Los hallazgos proporcionan información crucial sobre la compleja interacción que rige la superconductividad a alta temperatura.
Videos de Conceptos Relacionados
01:24Superconductor
1.9K
A substance that reaches superconductivity, a state in which magnetic fields cannot penetrate, and there is no electrical resistance, is referred to as a superconductor. In 1911, Heike Kamerlingh Onnes of Leiden University, a Dutch physicist, observed a relation between the temperature and the resistance of the element mercury. The mercury sample was then cooled in liquid helium to study the linear dependence of resistance on temperature. It was observed that, as the temperature decreased, the...
1.9K
01:28Types Of Superconductors
1.7K
A superconductor is a substance that offers zero resistance to the electric current when it drops below a critical temperature. Zero resistance is not the only interesting phenomenon as materials reach their transition temperatures. A second effect is the exclusion of magnetic fields. This is known as the Meissner effect. A light, permanent magnet placed over a superconducting sample will levitate in a stable position above the superconductor. High-speed trains that levitate on strong...
1.7K
01:31Ferromagnetism
2.8K
Materials like iron, nickel, and cobalt consist of magnetic domains, within which the magnetic dipoles are arranged parallel to each other. The magnetic dipoles are rigidly aligned in the same direction within a domain by quantum mechanical coupling among the atoms. This coupling is so strong that even thermal agitation at room temperature cannot break it. The result is that each domain has a net dipole moment. However, some materials have weaker coupling, and are ferromagnetic at lower...
2.8K
01:17Theory of Metallic Conduction
2.0K
The conduction of free electrons inside a conductor is best described by quantum mechanics. However, a classical model makes predictions close to the results of quantum mechanics. It is called the theory of metallic conduction.
In this theory, Newton's second law of motion is used to determine the acceleration of an electron in the presence of an applied electric field. Then, its velocity is expressed via this acceleration.
An electron moves through the crystal, containing positive ions,...
In this theory, Newton's second law of motion is used to determine the acceleration of an electron in the presence of an applied electric field. Then, its velocity is expressed via this acceleration.
An electron moves through the crystal, containing positive ions,...
2.0K
01:22Semiconductors
1.9K
There is variation in the electrical conductivity of materials - metals, semiconductors, and insulators that are showcased with the help of the energy band diagrams.
Metals such as copper (Cu), zinc (Zn), or lead (Pb) have low resistivity and feature conduction bands that are either not fully occupied or overlap with the valence band, making a bandgap non-existent. This allows electrons in the highest energy levels of the valence band to easily transition to the conduction band upon gaining...
Metals such as copper (Cu), zinc (Zn), or lead (Pb) have low resistivity and feature conduction bands that are either not fully occupied or overlap with the valence band, making a bandgap non-existent. This allows electrons in the highest energy levels of the valence band to easily transition to the conduction band upon gaining...
1.9K
01:24Metal-Semiconductor Junctions
1.4K
The contact of metal and semiconductor can lead to the formation of a junction with either Schottky or Ohmic behavior.
Schottky Barriers
Schottky barriers arise when a metal with a work function (Φm) contacts a semiconductor with a different work function (Φs). Initially, electrons transfer until the Fermi levels of the metal and semiconductor align at equilibrium. For instance, if Φm > Φs, the semiconductor Fermi level is higher than the metal's before contact. The...
Schottky Barriers
Schottky barriers arise when a metal with a work function (Φm) contacts a semiconductor with a different work function (Φs). Initially, electrons transfer until the Fermi levels of the metal and semiconductor align at equilibrium. For instance, if Φm > Φs, the semiconductor Fermi level is higher than the metal's before contact. The...
1.4K