Research On Photon Echo Characteristics Based On Modulation Pulse

With the increasing requirements of photon echo technology,the research on photon echo has become more and more urgent.The continuous development of photon echo model has enabled researchers to have more ways and more parameters to accurately control the generation.In addition to the significant significance of photon echo in the field of optical information,photon echo based storage also has important applications in all-optical communication technology,such as optical delay.Any signal generation technology based on photon echo has been widely used in ultra-high resolution radar,microwave and millimeter wave communication equipment,data storage and quantum information processing.For the application of photon echo,this paper has carried out the following work:1.The transient coherent effects is quantitatively analyzed by the analytical solution of Bloch equation.In optical nutation,using the Bloch sphere radius and Bloch vector azimuth,it is found that optical nutation can effectively maintain particle coherence,which is of great significance for optical storage in quantum optical communication technology.In the optical free induction decay,the beat frequency signal is used to obtain different frequency offset effects on the process.Finally,the Bloch vector solution and the transmission field expression of the photon echo are obtained,which lays a foundation for the subsequent research.2.A method of photon echo detection is proposed by using chirp pulse detection.Since the photon echo field is extremely weak,this paper uses the chirped pulse to detect the photon echo,which generates the chirped beat frequency signal,and studies the photon echo characteristics by observing the beat frequency signal.The beat frequency detection of single photon echo and multi-photon echo is carried out by using chirped pulse.The influence of chirp rate and delay time on beat signal is analyzed,and the factors affecting the efficiency of beat signal are discussed.3.In order to eliminate the influence of dynamic phase,a photon echo generation method with externally modulated pulses is proposed.In the traditional two-pulse photon echo configuration,three modulation pulses are added,and the geometric phase is introduced in the photon echo formation process,which eliminates the influence of dynamic phase in the cyclic evolution.In the microscopic mechanism,the Bloch ball is used to visually describe the motion trajectory of the Bloch vector after the applied modulated pulse.The finite element difference algorithm is used to analyze the photon echo generation process of the modulated pulse.The relationship between the modulation phase and the photon echo phase is analyzed,and the feasibility of adjusting the phase of the photon echo is verified.