Nematic colloidal micro-motors powered by light

Duration: 45 mins 1 sec
Share this media item:
Embed this media item:


About this item
media item has no image
Description: Smalyukh, I
Friday 17th May 2019 - 09:00 to 09:40
 
Created: 2019-06-12 12:52
Collection: Optimal design of soft matter - including a celebration of Women in Materials Science (WMS)
Publisher: Isaac Newton Institute
Copyright: Smalyukh, I
Language: eng (English)
Distribution: World     (downloadable)
Explicit content: No
Aspect Ratio: 16:9
Screencast: No
Bumper: UCS Default
Trailer: UCS Default
 
Abstract: Man-made nano- and micro-motors are key to many future applications. I will describe highly reconfigurable self-assembly of colloidal micro-motors that exhibit a repetitive rotation when immersed in a liquid crystal and powered by a continuous exposure to unstructured ~1nW light. A monolayer of self-assembled azobenzene molecules defines how the liquid crystal’s optical axis mechanically couples to the colloidal particle’s surface, as well as how they jointly rotate as the light’s polarization changes. The rotating particle twists the liquid crystal, which, in turn changes polarization of the light traversing it. The resulting feedback mechanism spontaneously yields a continuous opto-mechanical cycle and drives the unidirectional particle spinning, with handedness and frequency robustly controlled by polarization and intensity of light. I will discuss how this may enable new forms of active matter and self-assembled machines.
Available Formats
Format Quality Bitrate Size
MPEG-4 Video 640x360    1.93 Mbits/sec 654.08 MB View Download
WebM 640x360    0.98 Mbits/sec 332.69 MB View Download
iPod Video 480x270    520.65 kbits/sec 171.67 MB View Download
MP3 44100 Hz 249.74 kbits/sec 82.44 MB Listen Download
Auto * (Allows browser to choose a format it supports)