Guo Ru

Saturable Nonlinearity in Photovoltaic-Photorefractive Crystals Under Open-circuit Condition

We show that the refractive index change induced by a focused incident beam with an additional incoherent uniform illumination in photovoltaic-photorefractive crystals under open-circuit condition has a saturable nonlinearity form. The incoherent uniform background illumination can be used to increase the effective dark irradiance. The formation time of the photovoltaic soliton can be decreased by keeping the intensity of the soliton at a higher value without over-saturation by use of the background illumination.

Photodiffractive effects in semiconductor microstructures

We have investigated the photodiffractive effect induced by resonant excitations in semi-conductor microstructures by means of the multiple wave coupling method. We have derived a set of multiple wave coupling equations for photodiffractions in the case of coexistence of refraction and absorption gratings. Numerical results of the equations for a few typical cases have been analysed in detail, and their physical significance is also discussed.

Transient-State and Steady-State Light-Induced Scattering in Photorefractive Crystal LiNbO3: Fe

We found that drift-length of light-excited electrons L0 has influence upon the light-induced scattering in LiNbO3: Fe crystal. We proposed that one of the necessary conditions for steady-state light-induced scattering is D > L0 (where D is the illumination beam size).

Multi-Soliton in One Dimensional Coupled Bose-Fermi System

With a model of a modified field coupled to a Dirac field we obtain a multi-soliton and Corresponding fermion modes in the presence of the multi-soliton. The fermion number is also discussed.

P-IC-C Successive Transitions in Ferroelectrics-II, Type-II IC System

In this paper, we derive a general multi-harmonic modulation solution for the general model of Type-I IC systems, based on the point of view of an earlier paper of the authors. In two limit cases it reduces to single-harmonic modulation and kink solution respectively. The basic wave-vector of modulation decreases monotonically with temperature, which is in agreement with what were observed in experiments. The conditions and characteristics of the P-IC and IC-C transitions are also discussed.

The

In this paper, the projection of an field is used to describe the double-state system and obtain an collision solution, with which the self-consistent equations of electron wave-functions have apparent analytic solutions in two extreme cases.