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Galería de susurros topológicos no herméticos
Bolun Hu1, Zhiwang Zhang2, Haixiao Zhang1
1Department of Physics, MOE Key Laboratory of Modern Acoustics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China.
Nature
|September 30, 2021
Resumen
Los investigadores desarrollaron un aislante de galería topológica utilizando cristales sónicos y películas de nanotubos de carbono. Esta innovación permite la manipulación controlada de ondas sonoras para aplicaciones avanzadas de detección acústica y pruebas no destructivas.
Área de la Ciencia:
- Acústico
- Física de la materia condensada
- Ciencias de los materiales
Sus antecedentes:
- Las ondas de galería de susurros, observadas por Lord Rayleigh, exhiben una propagación de sonido eficiente alrededor de las curvas con una difracción mínima.
- Los avances recientes exploran la física no hermética y los aislantes topológicos para una nueva guía y control de ondas.
- Las aplicaciones incluyen pruebas ultrasónicas y detección óptica, destacando la importancia del control de los fenómenos de onda.
Objetivo del estudio:
- Para construir un aislante de galería topológica para manipular las ondas sonoras.
- Para diseñar no-hermiticidad para el control de los modos de galería de susurros.
- Para lograr "lasing de audio" direccional para aplicaciones acústicas avanzadas.
Principales métodos:
- Fabricación de un aislante topológico de galería utilizando cristales sónicos compuestos de varillas termoplásticas.
- Decoración de las barras con películas de nanotubos de carbono para crear un medio de ganancia sónica mediante acoplamiento electro-termoacústico.
- Ingeniería de texturas no herméticas para romper la simetría quiral y permitir el acoplamiento externo del modo.
Principales resultados:
- Construcción exitosa de un aislante de galería topológica.
- Demostración de la ruptura de la simetría quiral en los modos de galería de susurros a través de la no hermiticidad de ingeniería.
- Observación de los modos direccionales de "lasing de audio" con la mano deseada.
Conclusiones:
- El aislante de galería topológica desarrollado ofrece una nueva plataforma para controlar las ondas sonoras.
- Este trabajo allana el camino para avances en pruebas no destructivas y detección acústica.
- Los hallazgos conectan la física no hermética, los aislantes topológicos y la manipulación de ondas acústicas.
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