摘要
Optomechanics arises from the photon momentum and its exchange with low-dimensional objects.It is well known that optical radiation exerts pressure on objects,pushing them along the light path.However,optical pulling of an object against the light path is still a counter-intuitive phenomenon.Herein,we present a general concept of optical pulling-opto-thermoelectric pulling(OTEP)—where the optical heating of a light-absorbing particle using a simple plane wave can pull the particle itself against the light path.This irradiation orientation-directed pulling force imparts self-restoring behaviour to the particles,and three-dimensional(3D)trapping of single particles is achieved at an extremely low optical intensity of 10^(−2)mWμm^(−2).Moreover,the OTEP force can overcome the short trapping range of conventional optical tweezers and optically drive the particle flow up to a macroscopic distance.The concept of selfinduced opto-thermomechanical coupling is paving the way towards freeform optofluidic technology and lab-on-achip devices.
基金
the financial support of the National Science Foundation(NSF-CMMI-1761743)
the Army Research Office(W911NF-17-1-0561)
the National Aeronautics and Space Administration Early Career Faculty Award(80NSSC17K0520)
the National Institute of General Medical Sciences of the National Institutes of Health(DP2GM128446)
financial support of this work from the Robert A.Welch Foundation(Grant no.F-1464)
the National Science Foundation through the Center for Dynamics and Control of Materials:an NSF MRSEC under Cooperative Agreement No.DMR-1720595
support from the Youth Thousand Talent Programme of China.
