Self-pumped phase-conjugation properties of cerium-doped BaTiO(3) crystals in the near infrared

Studies of a new Ce-doped BaTiO(3) crystal as an efficient self-pumped phase conjugator in the near infrared are presented. The internal beam production during the establishment of self-pumped phase conjugation (SPPC) is closely observed, and the corresponding mechanisms of SPPC are identified accordingly. When the incident beam is in an a-face-incidence geometric arrangement, it is observed for the first time that SPPC mechanism has a transition from stimulated photorefractive backscattering and four-wave mixing to total internal reflection when λ is varied from 706 to 733 nm. Variations of the SPPC reflectivity with the λ, incident angle, and position of the input beam have been investigated, and a high reflectivity of approximately 80% has been obtained. In addition, SPPC reflectivity of approximately 40% is obtained when the incident beam enters the crystal by the +c face, and a variation with λ of optical beam patterns in the crystal has also been observed. Qualitative explanations of the phenomenon of SPP mechanism transition with λ that will be very useful in practical applications are given.

[Immunoelectronmicroscopic study of fibronectin in Kupffer's cell in rats with multiple organ failure]

This essay studied the content and distribution of Fibronectin (Fn) in Kupffer's cells in rats with multiple organ failure (MOF) with the immunoelectronmicroscopy technique. The results revealed that there was a significant increase in Fn level in plasma and the amount of immunogold particles in Kupffer's cells during the early stage, but the changes were not evident in the late stage. Our findings indicated that the changes in content of Fn was closely related to the function of MPS and might play an important role in the pathogenic mechanism of MOF.

Mechanism transformation with wavelength of self-pumped phase conjugation in BaTiO(3):Ce

We report what is to our knowledge the first observation of mechanism transformation with wavelength of self-pumped phase conjugation (SPPC) in BaTiO(3):Ce crystals in the near infrared. It was found that the SPPC mechanism changed from a backscattering and four-wave-mixing mechanism to a cat mechanism when the pump wavelength was varied from 706 to 770 nm. In addition, SPPC was obtained when the pump beam entered the crystal by the +c face, and a variation with wavelength of optical beam paths in the crystal was also observed.