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Micro-scale opto-thermo-mechanical actuation in the dry adhesive regime.

ABSTRACT: Realizing optical manipulation of microscopic objects is crucial in the research fields of life science, condensed matter physics, and physical chemistry. In non-liquid environments, this task is commonly regarded as difficult due to strong adhesive surface force (~µN) attached to solid interfaces that makes tiny optical driven force (~pN) insignificant. Here, by recognizing the microscopic interaction mechanism between friction force-the parallel component of surface force on a contact surface-and thermoelastic waves induced by pulsed optical absorption, we establish a general principle enabling the actuation of micro-objects on dry frictional surfaces based on the opto-thermo-mechanical effects. Theoretically, we predict that nanosecond pulsed optical absorption with mW-scale peak power is sufficient to tame µN-scale friction force. Experimentally, we demonstrate the two-dimensional spiral motion of gold plates on micro-fibers driven by nanosecond laser pulses, and reveal the rules of motion control. Our results pave the way for the future development of micro-scale actuators in non-liquid environments.

SUBMITTER: Tang W

PROVIDER: S-EPMC8458461 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature

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Micro-scale opto-thermo-mechanical actuation in the dry adhesive regime.

Tang Weiwei W Lyu Wei W Lu Jinsheng J Liu Fengjiang F Wang Jiyong J Yan Wei W Qiu Min M

Light, science & applications 20210922 1

Realizing optical manipulation of microscopic objects is crucial in the research fields of life science, condensed matter physics, and physical chemistry. In non-liquid environments, this task is commonly regarded as difficult due to strong adhesive surface force (~µN) attached to solid interfaces that makes tiny optical driven force (~pN) insignificant. Here, by recognizing the microscopic interaction mechanism between friction force-the parallel component of surface force on a contact surface- ...[more]

PMID: 34552048

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Micro-scale opto-thermo-mechanical actuation in the dry adhesive regime.

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Micro-scale opto-thermo-mechanical actuation in the dry adhesive regime.

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