Video Experimental Relacionado
Updated: Apr 23, 2026
09:06
Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
6.6K
Materia topológica. materia topológica. Observación de los fermiones de Majorana en cadenas atómicas ferromagnéticas
Stevan Nadj-Perge1, Ilya K Drozdov1, Jian Li1
1Joseph Henry Laboratories and Department of Physics, Princeton University, Princeton, NJ 08544, USA.
Science (New York, N.Y.)
|October 4, 2014
Resumen
Los investigadores crearon cadenas atómicas de hierro (Fe) en plomo (Pb) para realizar superconductores topológicos unidimensionales. Observaron evidencia de fermiones de Majorana, partículas exóticas que se predijo que existirían en los bordes de estos sistemas.
Área de la Ciencia:
- Física de la materia condensada Física de la materia condensada
- Ciencia de los materiales Ciencia de los materiales.
- La física cuántica es la física cuántica.
Sus antecedentes:
- Los superconductores topológicos albergan cuasipartículas exóticas como los fermiones de Majorana en sus bordes.
- Estos sistemas son cruciales para el avance de la computación cuántica y la física fundamental.
- Fabricar superconductores topológicos unidimensionales sigue siendo un desafío significativo.
Objetivo del estudio:
- Para realizar un superconductor topológico unidimensional.
- Para investigar la presencia de fermiones de Majorana en cadenas atómicas diseñadas.
Principales métodos:
- Fabricación de cadenas atómicas de hierro ferromagnético (Fe) en un sustrato de plomo (Pb) superconductor.
- Utilizando técnicas de imagen espectroscópica de alta resolución para sondear las propiedades electrónicas.
- Analizar la densidad electrónica de los estados e identificar firmas espectrales únicas.
Principales resultados:
- La superconductividad fue inducida en la mayor parte de las cadenas atómicas de Fe.
- Se observó la aparición de estados finales de energía cero en los bordes de la cadena.
- Estos estados finales proporcionan una fuerte evidencia de la formación de fase topológica.
Conclusiones:
- La configuración experimental creó con éxito las condiciones para un superconductor topológico.
- Se detectaron fermiones de Majorana en los bordes, confirmando las predicciones teóricas.
- Este trabajo allana el camino para nuevos dispositivos electrónicos cuánticos.
Videos de Conceptos Relacionados
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
01:28Types Of Superconductors
1.6K
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...
1.6K
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
01:17Theory of Metallic Conduction
1.9K
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,...
1.9K
01:05Atomic Nuclei: Magnetic Resonance
1.2K
The number of nuclear spins aligned in the lower energy state is slightly greater than those in the higher energy state. In the presence of an external magnetic field, as the spins precess at the Larmor frequency, the excess population results in a net magnetization oriented along the z axis. When a pulse or a short burst of radio waves at the Larmor frequency is applied along the x axis, the coupling of frequencies causes resonance and flips the nuclear spins of the excess population from the...
1.2K
01:23Atomic Nuclei: Nuclear Relaxation Processes
1.1K
In the absence of an external magnetic field, nuclear spin states are degenerate and randomly oriented. When a magnetic field is applied, the spins begin to precess and orient themselves along (lower energy) or against (higher energy) the direction of the field. At equilibrium, a slight excess population of spins exists in the lower energy state. Because the direction of the magnetic field is fixed as the z-axis, the precessing magnetic moments are randomly oriented around the z-axis.
1.1K