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Nudos y enlaces reconfigurables en coloides nématicos quirales
Uroš Tkalec1, Miha Ravnik, Simon Čopar
1Condensed Matter Physics Department, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia. uros.tkalec@ijs.si
Science (New York, N.Y.)
|July 2, 2011
Resumen
Los científicos utilizaron pinzas láser para atar nudos y enlaces microscópicos en cristales líquidos, creando complejas estructuras topológicas. Esto demuestra la topología.
Área de la Ciencia:
- Física de la materia blanda Física de la materia blanda
- Ciencia de los materiales Ciencia de los materiales.
- Topología de la topología.
Sus antecedentes:
- Es difícil anudar y vincular estructuras microscópicas en polímeros y líneas de defectos.
- Los defectos topológicos en los materiales son cruciales para sus propiedades.
Objetivo del estudio:
- Para demostrar el nudo y el enlace controlados de líneas de defectos topológicos microscópicos.
- Explorar el uso de pinzas láser para la micromanipulación de defectos topológicos.
- Para clasificar estas estructuras topológicas utilizando el número de autoenlace.
Principales métodos:
- Utilizó pinzas láser para una micromanipulación precisa.
- Se han creado nudos y enlaces en coloides de cristal líquido quiral nemático.
- Estructuras topológicas clasificadas por su número de autoenlace cuantizado.
Principales resultados:
- Formar con éxito nudos y enlaces de complejidad arbitraria, hasta seis cruces.
- Demostró estructuras topológicas complejas como el enlace de Hopf, la Estrella de David y los anillos borromeos.
- Particulas coloidales estabilizadas en configuraciones únicas de materia blanda.
Conclusiones:
- Las pinzas láser permiten la creación de complejos nudos y enlaces microscópicos en materia blanda.
- El número de autoenlace cuantizado clasifica estas estructuras topológicas.
- La topología es un factor clave en la ingeniería de materiales de materia blanda.
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