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Title: Efficiently Light-Controlled Reconfigurable Semiconductor Micromotors in Electric Fields
To develop active materials that can efficiently respond to external stimuli with designed mechanical motions is a major obstacle that have hindered the realization nanomachines and nanorobots. Here, we present our finding and investigation of an original working mechanism that allows multifold reconfigurable motion control in both rotation and alignment of semiconductor micromotors in an AC electric field with simple visible-light stimulation. In our previous work, we reported the instantly switchable electrorotation owing to the optically tunable imaginary part of electric polarization of a semiconductor nanowire in aqueous suspension[1]. Here we provide further experimental confirmation along with numerical simulation. Moreover, according to the Kramers-Kronig relation, the real part of the electric polarization should also be optically tunable, which can be experimentally verified with tests of electro-alignment of a nanowire. Here, we report our experimental study of light effect on electro-alignment along with theoretical simulation to complete the investigation of opto-tunable electric polarization of a semiconductor nanowire. Finally, we demonstrate a micromotor with periodically oscillating rotation with simple asymmetric exposure to a light pattern. This research could inspire development of a new class of micro/nanomachines with agile and spatially defined maneuverability.  more » « less
Award ID(s):
1710922 1150767
NSF-PAR ID:
10159664
Author(s) / Creator(s):
;
Date Published:
Journal Name:
MANIPULATION, AUTOMATION AND ROBOTICS AT SMALL SCALES. INTERNATIONAL CONFERENCE. 2019. (MARSS 2019)
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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