Optical Weak Measurement Technology And Its Application In Optical Phase Delay And Topological Charge Detection

In recent years,optical weak measurement technology has attracted widespread attention as an emerging measurement technology.Thanks to the weak value amplification effect,weak measurement technology can effectively amplify small physical quantities.In addition,this measurement technology has the characteristics of high accuracy,simple measurement system,low cost,and no damage.As a result,a large number of researches have been carried out to apply this technique for measuring beam offset,beam angular displacement,and optical time shift.Because these optical physical quantities are very sensitive to the outside world,a large number of researches using this technology for sensing have emerged.Until now,optical weak measurement technology has made great achievements in the fields of precision measurement,biosensing,and quantum information.With the development of modern science and technology,new detection technologies have been required to be more precise and sensitive.Therefore,further research on this technology will have far-reaching significance and important application prospects.The research work of this paper is focused on the application of optical weak measurement technology to detect optical phase delay and.Optical phase is an important physical quantity describing a light beam.Firstly,the phase delay detection based on optical weak measurement technology is first studied in this paper.By building a weak measurement system and establishing a suitable preselection and postselection state,the tiny phase delay is amplified.The phase delay is characterized by the peak shift of the spectrum.In the experiment,it was found that when the post selection deviates from the orthogonal position by 0.219°(?=0.219°),the peak of the spectrum moves the fastest and the highest accuracy,which is the best post selection.Under the best weak measurement conditions,the maximum phase delay measurement accuracy is obtained.On the other hand,the core research work of this thesis is vortex topological charges detection based on optical weak measurement technology.The vortex topological charges are detected by detecting the small lateral beam shift caused by the Orbital Angular Momentum Hall Effect.Under the same conditions,the beam shift of the vortex light carrying different topological charges is different at the interface.This characteristic can be used to measure the topological charges.In the theory,the weak-amplification theory of vortex-induced displacement was first studied.It was found that by carefully designing the preselection and postselection for the weak measurement system,the topological charges dependent shift was amplified.Secondly,the weak-amplification theory of beam shift induced by topological charges is studied in combination with wave optics theory.The relationship between the components X_wand Y_wof the light centroid in the x and y directions and pre/post-selection is obtained by simulation.Finally,the amplified topological charges induced displacement was optimized.The relationship between the incident angle of vortex light and the beam shift was studied.In the experiment,an experimental device using for weak measurement amplified beam shift to determine topological charge?was built.At Brewster angle,the best preselected state of weak measurement is obtained through experiments.Secondly,it is found that when the maximum beam shift is 42.3?m,topological charge?is 1;when the maximum displacement is 90.7?m,topological charge?is 3;when the maximum displacement is 121.2?m,topological charge?is 5;Thus,the determination of the topological charge is realized.The innovations of the research work in this paper are as follows:(1)Weak value amplified mechanism of Beam shift Induced by topological charge is figured out.The optimal preselection and postselection state of the weak measurement system is figured out.(2)Experimentally,the topological charge induced beam shift at the interface has been amplified using an optical weak measurement system.(3)The topological charge was measured by measuring the beam shift experimentally.