Optical Tractor Force In Two Dimensional Photonic Crystal Background

As everyone knows，object will has an optical press when act with light. While inrecent years, people found that light can give the object a force opposite to the directionof light propagation in some special situation. And we call this force oprical tractorforce.This anti physical intuition phenomenon attract peoples’ great interest. Althoughpeople found the phenomenon of optical tractor force and verify the feasibility to getoptical pulling force in theory，the nature of optical tractor beam and the rules of theinteraction of light and matter still need to be found.Right now, realize optical tractor force mostly by tailoring the source or tailoringthe object, while we think tailoring the background can realize the optical tractor force.So in our investigation, we discuss optical tractor force in a periodic background. In themodel of optical tractor force in a periodic background, we reasch the nature of opticaltractor force.Firstly, we built the optical tractor force model of photonic crystal self-collimationmode. In this mode, an ellipsoid may be given an optical tractor force. Then analysis thereason of optical tractor force from momnetum conservation. Because scattering ofellipsoid, the self-collimation mode has a new arrangement in energy, while the widthof beam is limited by periodic background. Actually, negative optical scattering forceby adiabatic beam width tailoring act as optical tractor force in this model.Secondly, we built the optical tractor force model of photonic crystal waveguideattenuation mode. The kind of weakly scattering spheres may be given an optical tractorforce. Analysis the reason of optical tractor force from optical gradient force. In weaklyscattering situation, just consider optical gradient force, while the propagation constantof attenuation mode in this model is a pure imaginary number. The optical gradientforce only direction towards to the light source act as optical tractor force.Finally, we built a structure that can bend route of optical manipulation, andrealized the totally opposite result to optical clearing. Optical clearing use the flexuralproperty of airy beam and radiation press, and we call this optical straw. While thisprovide a new idea to optical manipulation.In conclution, in our investigation we built two new model to get optical tractorforce, anaylysis the reason to make optical tractor force correspondent, and design anew way of optical micro control that opposite to optical clearing. Our work abound therealize of optical tractor force and gives a new idea to optical micro control.Our workhelp to understand optical tractor beam, and the nature of interaction of light and matter.