The poly-[2-methoxy,(5-2′-ethyl-hexyloxy)-p-phenylene vinylene](MEH-PPV) film is investigated by means of the Multi-Color Photon Echo(MCPE) technique. Under the three-order nonlinear response theory,the reason for the occurrence of the quantum beats in the time domain and the relations among signal wavevector,pulse sequence and response function are discussed. The analysis of the Raman spectrum of MEH-PPV and the fast Fourier transformation(FFT) results of photon echo(PE) signal dynamics demonstrate the coherent coupling between the C==C bonds and the CC-H bonds and the coherent coupling between the C-C stretching of the phenyl group and the C==C stretching of the vinylene group.
YU GuoYang 1 ,SONG YunFei 1 ,WANG YingHui 1 ,LIU YuQiang 1 ,MO YueQi 2 & YANG YanQiang 1 1 Center for Condensed Matter Science and Technology,Department of Physics,Harbin Institute of Technology,Harbin 150001,China
