Jiang Quanzhong

Coherent Mutually Pumped Phase Conjugation Induced with High-Efficiency by Self-Pumped Phase Conjugate Reflection

A new scheme of coherent mutually pumped phase conjugate (MPPC) reflection that depends on the formation of self-pumped phase conjugate reflection of another beam has been demonstrated in a Cu:KNSBN crystal. The dependences of the MPPC reflectivity on the intensity ratio of the two incident beams and on the incident position of the signal beam were measured. We obtain phase conjugate reflectivities of greater than 90% at 488 nm.

Growth and two-wave coupling properties of potassium sodium strontium barium niobate with A-sites not fully-occupied

This paper reports the growth and two-wave coupling properties of (K0.5-Na0.5)2z (Sr0.75Ba0.25)1-xNb2O6(z=0.1, 0.05 and 0.03) crystals. Comparing to the others, the crystal at z=0.05 has shorter response time and larger two-wave coupling gain coefficient. The gain coefficient of it surpasses that of SBN:Ce.

Effect of light-induced scattering on diffraction efficiency in photorefractive crystals

The coupled wave equations and their analytic solutions in photorefractive crystals are presented for the case of two-beam writing, while the light-induced scattering is considered. Using this result, the diffraction efficiency for each writing beam is discussed in doped KNSBN crystals with unidirectional fan, which is explained theoretically and verified experimentally.

Simulating study on internal self-pumped phase conjugators with external configurations

A new method is proposed to study the properties of stimulated photorefractive backscattering and four-wave-mixing (SPB-FWM) and total-internal-reflection (TIR) self-pumped phase conjugators. The phase conjugators are simulated with external configurations using a KNSBN:Cu crystal, a plane mirror and a prism. As a result, the parameters such as beamwidth and intensity of the contra-directionally propagating pump beams for the FWM interactions in the crystal can be easily controlled. The dependence of self-pumped phase conjugation reflectivity and FWM coupling strength on these parameters of the pump beams have been studied.

Growth and High Reflectivity Self-Pumped Phase Conjugate of Cu-Doped KNSBN Crystal

The Cu-doped KNSBN crystals have been grown. The self-pumped phase conjugate mirrors of Cu-doped KNSBN crystals have been demonstrated. The phase conjugate reflectivity reaches as high as 68% for the crystal with 0.04 wt.% Cu-doped. The phase conjugate reflectivity and its response time were also measured as a function of the argon-ion laser wavelengths.

Self-Pumped Phase Conjugation of Co-Doped (KNa)0.1 (Sr0.75Ba0.25)0.9Nb2O6 Crystal

Self-pumped phase conjugate in trapezoid-cut Co-doped (KNa)0.1 (Sr0.75Ba0.25)0.9Nb2O6 (Co-KNSBN) crystal was demonstrated without external reflection mirrors and applied field, phase conjugation reflectivities as high as 40.5% were measured. The threshold power was lower than 0.02 W/cm2. The device was operated in one-region four-wave mixing using the photorefractive effect.

GROWTH AND PHOTOREFRACTIVE PROPERTIES OF KNSBN:Co CRYSTAL

Growth and photorefractive properties of KNSBN:Co crystal are reported for the the first time.Crystals were grown by CZ technique and the growth habits of them are severly affected by the amount of Co ions.New energy levels are formed in the energy band gap. Comparing to undoped KNSBN, KNSBN:Co has larger two-wave coupling coefficient, shorter response time and larger photo-induced free electron concentration in the experiment of two-wave coupling. Phase conjugation reflectivity of 56% and response time of 150ms were determined in the experiment of degenerate four-wave mixing.

Studies on photorefractive crystal lead barium niobate

The optical quality Pb1-xBaxNb2O6 single crystals have been grown by Czochraski method from the melt. Their structure, dielectric, ferroelectric properties were studied. Transmission spectra, two-wave mixing properties were measured. This crystal will be an available material for photorefractive applications.