| The speed of light propagation is known to be the fastest in nature,so the application of photons in information transmission and measurement has its absolute advantages.It is not only the speed of propagation,but also the advantages of stability,anti-interference,etc..It also determines that photons are superior to other substances as ideal carriers of information transmission.The quantum interference effects of coherent light fields and atomic excitation play an important role in quantum Metrology and quantum information science.In recent years,electromagnetic induction transparency?EIT?technology has been widely used in many aspects.Based on this,the optical storage experiment is of great significance to realize the full quantum information transfer.Based on the experiment of optical storage,the optical interference of signal pulse due to overlay is further studied.This process is carried out in the hot helium atomic steam sample pool.In order to improve the storage efficiency and the stability of the experimental environment,a laser locking system is established to effectively lock the laser frequency to achieve synchronous oscillations from the laser frequency.The main content of this thesis is the experimental study of the optical stem based on transparent storage of electromagnetic induction involving the relevant laser locking system.The first part:the electromagnetic induction transparency effect and other related knowledge combing.This paper introduces the physical meaning of quantum interference effect and the energy level action relationship and principle of EIT phenomenon in the three-level model adopted in this paper.This paper introduces the historical research process and development of optical storage experiment based on the transparency of electromagnetic induction.The timing model of optical storage and optical interference based on electromagnetic induction transparency is described.The second part:The improvement of the experimental device system.This part focuses on the innovative ideas used in the experiment and the impact of the experimental instruments on the experiment itself.It is divided into two parts.Part of the experiment is to add the influence of the power amplifier on the experiment and the method of use of the amplifier.After adding the amplifier,the strength of the coupled field beam is increased,not only for the efficiency of EIT,but also for the efficiency of optical storage.Good help,It is more beneficial to study the interference phenomenon caused by the superposition of signal pulses.The other part is the implementation of the injection locking method.Through the connection of optical fiber modulators,frequency synthesizers,amplifiers,and other instruments with the optical path,the frequency of the two lasers is locked,so that the frequency difference between the winner and the laser is always maintained at the frequency value of 6.835GHz required for the experiment.The overall optical path is maintained in a very stable state,which is conducive to the subsequent experiments.The third part:Experimental research on optical interference based on transparent storage of electromagnetic induction.Based on the energy level analysis,the reason of using 87Rb Atom for experiment and the detailed explanation for the construction of experimental light path are described.This experiment is realized under the condition of high helium atomic vapor temperature,and using the acoustic light modulator?AOM?to modulate the light beam of the detection field and the coupling field by a level+1 light spot experiment,so that the detection field and the coupling field beam simultaneously occur.200M blue shift.Two photon resonances occur in the sample pool by adjusting the frequency of two lasers by injection locking method.Changing the storage time,the size of the extracted pulse signal will change,and it is concluded that the longer the storage time,the lower the efficiency,and the same results as expected.On this basis,the optical interference phenomenon is generated by the overlay of the pulse signal and the extracted signal.At the same time,this experiment provides some ideas for future experiments to increase the interference of multi-beam pulse signals. |
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