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Las huellas digitales temporales y espectrales de la conmutación de espín totalmente coherente ultrarrápida

S Schlauderer¹, C Lange², S Baierl¹

¹Department of Physics, University of Regensburg, Regensburg, Germany.

|May 17, 2019

Resumen

Los investigadores demuestran pulsos electromagnéticos de terahertz para la conmutación de espín coherente en la ortoferrita antiferromagnética de tulio. Este avance permite el control de baja pérdida y alta velocidad de los estados de espín cuántico para la futura tecnología de la información.

Área de la Ciencia:

El control cuántico
La tecnología Spintronics
Física de la materia condensada

Sus antecedentes:

La tecnología de la información del futuro requiere un control cuántico más rápido y de baja pérdida.
Los campos de luz intensos han impulsado el progreso en nuevos estados de la materia y la aceleración de electrones.
Cambiar los estados de espín cuántico de manera eficiente es crucial pero desafiante.

Objetivo del estudio:

Para demostrar la dirección coherente de los giros sobre una barrera potencial utilizando pulsos de terahertz.
Observar y caracterizar la dinámica de giro durante este proceso de conmutación.
Para explorar el potencial de los dispositivos de espín escalables que operan a velocidades de terahercios.

Principales métodos:

Utilizando intensos pulsos electromagnéticos de terahercios con una duración de un picosegundo.
Giros de acoplamiento en ortoferrita antiferromagnética de tulio (TmFeO3) con un campo eléctrico de terahercios mejorado localmente.
Empleando antenas personalizadas para generar y enfocar el campo de terahertz.

Principales resultados:

Se observa la dirección coherente de los giros sobre una barrera potencial.
Identificación de huellas temporales y espectrales de la dinámica de espín, incluido un cambio de fase y división de resonancia asimétrica.
Demostró que los estados conmutables pueden ser seleccionados por un sesgo magnético externo.

Conclusiones:

Los pulsos de terahercios permiten una conmutación de espín coherente eficiente y de baja disipación.
Los fenómenos observados proporcionan características para la comprensión de la dinámica de espín.
Este enfoque es prometedor para el desarrollo de dispositivos espintrónicos escalables que operan a frecuencias de terahercios.

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