Study on the Phase Dynamics of Macroscopic Polarization by Nonlinear Interferomer

非线性干涉体宏观偏振相动力学研究

基本信息

批准号：
05452066
负责人：
GONOKAMI Makoto
金额：
$ 4.48万
依托单位：
The University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (B)
财政年份：
1993
资助国家：
日本
起止时间：
1993 至 1994
项目状态：
已结题

项目摘要

In order to explore the mechanism of ultrafast coherent third order nonlinear responses in solid materials, we have developed a method to detect the coherent motion of macroscopic polarization created by the optical excitation. By this method, we can investigate phase coherence of resonantly excited excitons and biexcitons in inorganic and organic materials.1)Nonlinear InterferometerWe have proposed a scheme to measure the coherence of third-order nonlinear polarization by detecting the interference of degenerate four-wave mixing signal and reference optical pulses which were also from the same light source used to create coherent excitation of nonlinear polarization. With this set-up, we have detected the coherent oscillation of nonlinear polarization.2)Observation of Coherent Oscillation of Biexcitons in CuClThe coherent oscillation of biexcitons under the resonant two-photon excitation by femtosecond pulses has shown that the coherent oscillation continues up to 50 picosecond.3)Inte … More rference of Scalar Biexciton WavesWe have observed the interference of two biexciton waves which were excited by the orthogonally polarized pump beams. This indicates that the biexciton wave has the scalar wave nature. This is, to the best of our knowledge, the first time observation of scalar wave interference in solids.4)Detection of two-exciton coherence in GaAs quantum wellWe have applied the above methods to the 2D quantum well excitons which do not have stable biexciton state. We have clearly observed 2-f coherent oscillation which decays within 3 picosecond.5)Free Induction Decay of 2D Excitons in Anthracence crystalsBy using the coherent pump-probe spectroscopy, we have observed coherent oscillation signal of surface excitons in an anthracence crystal. We have examined the role of cooperative radiation decay of surface excitons, which is known as superradiative decay of 2D excitons.6)Degenerate Four Wave Mixing of Exciton-Cavity Coupled SystemWe have studied the linear exciton-photon coupling effect on the coherent nonlinear optical responses of excitons in 2D quantum well embedded in a semiconductor microcavity. We have observed that the strong confinement of photons inside the cavity enhances the coherent noonlinear responses. In the case of strong exciton-photon coupling, the formation of cavity polartons affects the coherent oscillation of excitonic polarization. We have developed a theoretical model to describe such phenomena based on the weakly interacting boson model. Less

为了探索固体材料中超快三阶响应的机制，宏观极化是通过可以在无机和有机材料中共同兴奋的相互兴奋剂和biexciton的相干性而产生的。退化的四波混合信号和参考光脉冲也来自与检测到的相干振荡的相同振动的相同光源。连贯的振荡持续到50个picsecond。固体中的标量波干扰。4）检测GAAS量子EllWe中的两种外激体相干性已将上述方法应用于2D量子井井中激素，这些井中不稳定的Bienciton状态，我们清楚地观察到了3 picosecond.5）。5） 2D激子的自由行业通过结合泵探针光谱的晶体，我们观察到炭疽晶体中的表面激子的振荡信号。在半导体微腔中嵌入的2D量子中激素的相干非线性反应。激子极化的相干振奋性。