Video Experimental Relacionado
Updated: Jun 18, 2026
09:00
Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
Creación eléctrica de la polarización de espín en silicio a temperatura ambiente
Saroj P Dash1, Sandeep Sharma, Ram S Patel
1MESA+ Institute for Nanotechnology, University of Twente, 7500 AE Enschede, The Netherlands.
Nature
|November 27, 2009
Resumen
Este estudio demuestra la inyección y detección de espín eléctrico a temperatura ambiente en silicio de tipo n y tipo p. Este avance permite la espintrónica de silicio a temperaturas ambientales para dispositivos nanoelectrónicos avanzados.
Área de la Ciencia:
- Física de los semiconductores Física de los semiconductores
- Spintronics es una empresa de Spintronics.
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- Spintronics utiliza el espín de electrones para la información digital, lo que podría revolucionar la nanoelectrónica.
- La manipulación de espín actual en semiconductores se limita a bajas temperaturas (<150 K) y materiales de tipo n.
Objetivo del estudio:
- Para demostrar la inyección de espín eléctrico a temperatura ambiente y la detección en silicio.
- Para permitir la funcionalidad espintrónica tanto en silicio de tipo n como en silicio de tipo p a temperatura ambiente.
Principales métodos:
- Inyección de espín eléctrico desde un túnel ferromagnético en contacto con el silicio.
- Manipulación del giro a través del efecto Hanle.
- Detección eléctrica de la acumulación de espín inducida.
Principales resultados:
- Se logró la inyección de espín a temperatura ambiente en silicio de tipo n y tipo p.
- Se ha demostrado una división de espín de hasta 2,9 meV en silicio de tipo n (polarización del 4,6%).
- La vida útil del espín extraído es >140 ps (electrones) y >270 ps (agujeros) a 300 K.
- Determinadas longitudes de difusión de espín >230 nm (electrones) y >310 nm (agujeros).
Conclusiones:
- Este trabajo allana el camino para los dispositivos espintrónicos de silicio que funcionan a temperatura ambiente.
- Permite la exploración de la funcionalidad de espín en dispositivos y circuitos de silicio complementarios.
- Proporciona información sobre el comportamiento fundamental del espín en el silicio en condiciones ambientales.
Videos de Conceptos Relacionados
01:03Atomic Nuclei: Nuclear Spin State Overview
NMR-active nuclei have energy levels called 'spin states' that are associated with the orientations of their nuclear magnetic moments. In the absence of a magnetic field, the nuclear magnetic moments are randomly oriented, and the spin states are degenerate. When an external magnetic field is applied, the spin states have only 2 + 1 orientations available to them. A proton with = ½ has two available orientations. Similarly, for a quadrupolar nucleus with a nuclear spin value of one, the...
01:14Atomic Nuclei: Nuclear Spin State Population Distribution
Near absolute zero temperatures, in the presence of a magnetic field, the majority of nuclei prefer the lower energy spin-up state to the higher energy spin-down state. As temperatures increase, the energy from thermal collisions distributes the spins more equally between the two states. The Boltzmann distribution equation gives the ratio of the number of spins predicted in the spin −½ (N−) and spin +½ (N+) states.
01:20Types of Semiconductors
Intrinsic semiconductors are highly pure materials with no impurities. At absolute zero, these semiconductors behave as perfect insulators because all the valence electrons are bound, and the conduction band is empty, disallowing electrical conduction. The Fermi level is a concept used to describe the probability of occupancy of energy levels by electrons at thermal equilibrium. In intrinsic semiconductors, the Fermi level is positioned at the midpoint of the energy gap at absolute zero. When...
01:08Spin–Spin Coupling Constant: Overview
In bromoethane, the three methyl protons are coupled to the two methylene protons that are three bonds away. In accordance with the n+1 rule, the signal from the methyl protons is split into three peaks with 1:2:1 relative intensities. The methylene protons appear as a quartet, with the relative intensities of 1:3:3:1.
Qualitatively, any spin plus-half nucleus polarizes the spins of its electrons to the minus-half state. Consequently, the paired electron in the hydrogen–carbon bond must have a...
Qualitatively, any spin plus-half nucleus polarizes the spins of its electrons to the minus-half state. Consequently, the paired electron in the hydrogen–carbon bond must have a...
01:28Induced Electric Dipoles
A permanent electric dipole orients itself along an external electric field. This rotation can be quantified by defining the potential energy because the external torque does work in rotating it. Then, the potential energy is minimum at the parallel configuration and maximum at the antiparallel configuration. While the former is a stable equilibrium, the latter is an unstable equilibrium.
Since the absolute value of potential energy holds no physical meaning, its zero value can be chosen as per...
Since the absolute value of potential energy holds no physical meaning, its zero value can be chosen as per...
01:31Dielectric Polarization in a Capacitor
The presence of a dielectric medium in a capacitor not only changes the voltage and capacitance but also affects the electric field. In general, dielectrics can be of two types: polar and nonpolar. In a polar dielectric, the positive and negative charges in the molecules are separated by a distance and hence have a permanent dipole moment. In contrast, no such charge separation exists in a nonpolar dielectric, however the nonpolar molecules get polarized in the presence of an external electric...