The positions of the side peaks and the character of symmetry of radiation spectrum depend upon the coherent excitation direction and the squeezing direction of the driving field.

meanwhile it excites coherently the elementary excitations of the crystal, the latter scatter the SHG into Stokes and antistokes radiations resulting in a complex effect of x(2) and x(3) nonlinear optical process.

A new method of designing MQ excitation pulse-sequences with high efficiency and coherences of the highest order Pmax = N , where N is the total spin number, is proposed. According to the different spin coupling networks, the pulse sequences were designed by the bilinear rotation pulses as basic excitation elements. The relations between the pulse sequences and the spin coupling networks were established and can be applied to the simplification of complex spectra and confirmation of coupling networks.

Above phenomena mean that the coherent vibration modes can be excited by stimuli of certain doses of He-Ne laser and non-linear dynamical interactions within biological cells.

This paper is the second part of a theory of the coherent propagation of light wave in semiconductors. After considering the interaction between electrons, the problem of a semiconductor interacting with light is discussed and the equation of exciton polarization wave excited by light wave is obtained. We point out that the equation can be approximated by a set of linear ones and the exciton polarization wave can be regarded as a Bose field only in the limit of low excitation. In this paper, the problem of coherent...

This paper is the second part of a theory of the coherent propagation of light wave in semiconductors. After considering the interaction between electrons, the problem of a semiconductor interacting with light is discussed and the equation of exciton polarization wave excited by light wave is obtained. We point out that the equation can be approximated by a set of linear ones and the exciton polarization wave can be regarded as a Bose field only in the limit of low excitation. In this paper, the problem of coherent excitation of discrete exciton level is also discussed specifically. It is shown that the discrete exciton level system excited coherently is approximately equivalent to a two-level atom system excited by light wave in which the difference of energy level is dependent on the degree of excitation and the density of equivalent "two-level atoms'' is determined by features of the exciton state wave function.

By pumping a LiIO3 crystal with 1.06μm picosecond laser pulses train at a proper incident angle, 8 stimulated Raman scattering lines have been obtained at the visible region from 4896 A to 6119A:ω=2ω1±nωP, n = 1, 2, 3, concerned elementary excitations being LO mode and TO mode of (A+E1) oblique polariton in the crystal. The process of such a complex stimulated Raman scattering is as following: with phase matching intense 1.06?m laser beam and its scattering light generate SHG in the crystal;meanwhile it excites...

By pumping a LiIO3 crystal with 1.06μm picosecond laser pulses train at a proper incident angle, 8 stimulated Raman scattering lines have been obtained at the visible region from 4896 A to 6119A:ω=2ω1±nωP, n = 1, 2, 3, concerned elementary excitations being LO mode and TO mode of (A+E1) oblique polariton in the crystal. The process of such a complex stimulated Raman scattering is as following: with phase matching intense 1.06?m laser beam and its scattering light generate SHG in the crystal;meanwhile it excites coherently the elementary excitations of the crystal, the latter scatter the SHG into Stokes and antistokes radiations resulting in a complex effect of x(2) and x(3) nonlinear optical process. Furthermore the reflected ward stimulated Raman scattering with distinct wavelength has been observed from the forward one. Present paper shows that the reflectedward scattering is also the SHG coherent Raman mixing but generated by the 1.06μm beam reflected upon the exit crystal surface.

In this paper coherent excitation of two-photon resonance in three-level systems is discussed. Under the condition of two ultrashort pulses with the same waveform, analytical solution of Blochequations of two-photon resonance, level-population and expression of excitation rate in three-level systems have been derived. Conditions for full inversion of population and maximal excitation rate have been obtained. With average-field approximation, analytical solutions of Bloch equations of two-photon off-resonance...

In this paper coherent excitation of two-photon resonance in three-level systems is discussed. Under the condition of two ultrashort pulses with the same waveform, analytical solution of Blochequations of two-photon resonance, level-population and expression of excitation rate in three-level systems have been derived. Conditions for full inversion of population and maximal excitation rate have been obtained. With average-field approximation, analytical solutions of Bloch equations of two-photon off-resonance have been obtained. The analytical expression of isotope coherent selective excitation coefficient has been deduced. Theoretical calculations show that the coherent excitation of two-photon resonance has a very high isotopic selectivity.