Since Arthur Ashkin and coworkers found that focused laser beam could displace and levitate microsized particles, optical tweezers has turn out to be a reliable noncontact tool for 3D manipulation of micro-objects, allows sensing by using only a single particle. The further development of nanophotonics toward higher sensitivities and resolutions continues to stimulate optical trapping of smaller and smaller objects. While applied to sub 100 nm-particles, the optical force starts to get insufficient to trap or manipulate, and the trap potential starts to be comparable to the thermal energy. Although there are a lot of methods that have been proposed to enhance the optical force, few research gets insight of the temperature effect on optical trapping. In this work, we summarize our recent experimental results on thermal sensing experiments in which micro/nanoparticles are used as probes with the aim of providing a contemporary state-of-the-art about the temperature effects in the stability of potential trapping processes.
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