Self - propelled particles driven by light
نویسنده
چکیده
In dieser Arbeit untersuche ich die wesentlichen Eigen-schaften biologischer und künstlicher aktiver Systeme undstelle eine neue Technik zur Herstellung von selbstgetriebe-nen mikroskopischen Kolloiden vor. Um den Antrieb zuerhalten nutzen wir phoretische Kräfte, welche ins Spielkommen, wenn ein Janus-Teilchen seine Umgebung asym-metrisch verändert. Erheblicher experimenteller Aufwandwird der Entwicklung aktiver Kolloide gewidmet, welchesich näherungsweise als selbstgetriebene harte Kugeln ver-halten. Dies ermöglicht es uns, die Rolle der aktiven Be-wegung hinsichtlich ihrer Phänomene unter komplexerenBedingungen zu untersuchen. Zur Unterstützung unsererexperimentellen Erkenntnisse vergleichen wir diese mit nu-merischen Simulationen von miteinander wechselwirkendenharten Kugeln. Tatsächlich beobachten wir, dass die Nicht-gleichgewichtsphysik, welche diese aktiven Objekte beschreibt,voller neuer und überraschender Besonderheiten steckt.
منابع مشابه
Trapping of interacting propelled colloidal particles in inhomogeneous media.
A trapping mechanism for propelled colloidal particles based on an inhomogeneous drive is presented and studied by means of computer simulations. In experiments this method can be realized using photophoretic Janus particles driven by a light source, which is partially blocked by a shading mask. This leads to an accumulation of particles in the passive part. An equation for an accumulation para...
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