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Generación de excitones-polaritones topológicos helicoidales

Wenjing Liu¹, Zhurun Ji¹, Yuhui Wang¹

¹Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, PA 19104, USA.

Science (New York, N.Y.)

|October 9, 2020

Resumen

Los investigadores demuestran polaritones topológicos robustos a temperatura ambiente sin campos magnéticos. Este avance en la fotónica topológica permite la propagación quiral sin dispersión para dispositivos ópticos y cuánticos avanzados.

Área de la Ciencia:

Fotónica topológica
Interacciones luz-materia
Física de la materia condensada

Sus antecedentes:

La fotónica topológica ofrece dispositivos ópticos robustos.
Los polaritones topológicos prometen una propagación quiral sin dispersión.
Las realizaciones experimentales anteriores requerían temperaturas criogénicas y campos magnéticos.

Objetivo del estudio:

Para demostrar polaritones topológicos helicoidales a temperaturas más altas y sin campos magnéticos externos.
Para explorar su potencial para dispositivos ópticos robustos y ajustables.

Principales métodos:

Acoplamiento de excitones monocapa WS2 a un cristal fotónico.
Utilizando la simetría de pseudo-reversión del tiempo para la protección topológica.
Operando a temperaturas de hasta 200 grados Kelvin.

Principales resultados:

Demostración exitosa de polaritones topológicos helicoidales hasta 200 K.
Naturaleza helicoidal verificada con polaritones de helicidad opuesta que se propagan en direcciones opuestas.
Elimina la necesidad de campos magnéticos fuertes.

Conclusiones:

Los polaritones topológicos helicoidales se pueden realizar en condiciones ambientales.
Este trabajo proporciona una plataforma para el desarrollo de dispositivos espintrónicos polaritónicos robustos.
Aplicaciones potenciales en el procesamiento de información clásica y cuántica.

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