Higher order off-resonat optical processes for homogeneous and inhomogeneous broadening of liquids

研究了凝聚相分子系统在飞秒激光脉冲作用下的非线性光学响应，研究了非共振激光作用下液态分子的非均匀展宽和振动模的非谐性.本文用路径积分法导出了非谐系统的五阶响应函数的解析表达式。应用这个方程，我们研究了非谐性和不均匀性之间的相互作用。导出了位移非简谐系统的五阶响应函数，并将其应用于光子回波、泵浦探测实验和新近发展的探测势弱非简谐性的五阶实验，利用量子Fokker-Planck方程研究了莫尔斯势系统的高阶光学过程。这个福克-普朗克方程可以处理任何形状的势耦合到高斯白或高斯马尔可夫噪声浴的分子系统。我们 关于我们 提出了一种计算三阶和五阶响应函数的方法，它们与分子坐标的二阶和三阶相关函数是等价的。运动的方法。假定铯二聚体的势面是由莫尔斯势模拟的，极化率与坐标的线性和非线性关系，我们计算了不同温度和热浴耦合下的三阶和五阶响应函数。通过绘制五阶光谱中的两个时间演化周期，得到了信号的二维轮廓。这些2D配置文件是敏感的形状的潜在的和极化率，即使是一个强阻尼的情况下，并依赖于温度。这表明，五阶二维光谱进行了不同的温度，使我们能够访问的潜力和极化率的信息。我们还提出了多态系统的Fokker-Planck方程，并将其应用于位移莫尔斯振子系统。观察并讨论了它的光学斯塔克效应。少

The nonlinear optical response of a molecular system in the condensed phase subjected to a series of off-resonant femtosecond laser pulses has been studied to investigate inhomogeneous broadening of liquid states and anharmonicity of vibrational modes. We have derived analytical expressions of the 5th order response function for an anharmonic system using path-integral techniques. Applying this equation, we have studied the interplay between anharmonicity and inhomogeneity. The fifth-order response function for a displaced anharmonic system has been also derived and applied to study photon echo, pump-probe experiments and newly developed the fifth-order experiment which is designed to detect weak anharmonicity of potentials.Using a quantum Fokker-Planck equation, we have studied higher-order optical processes of Morse potential systems. This Fokker-Planck equation can treat a molecular system with any shape of potential coupled to a Gaussian-white or a Gaussian Markovian noise-bath. We … More have presented a procedure to calculate the third-and fifth-order response functions, which are equivalent to the second-and third-order correlation functions of the molecular coordinate, by way of the eq. of motion approach. Assuming the potential surface of a Cesium dimer, which is modeled by the Morse potential, and the linear and nonlinear coordinate dependence of the polarizability, we calculated the third-and fifth-order response functions for various temperatures and heat-bath couplings. By plotting two time-evolution period involved in the fifth-order spectroscopy, we obtained the two-dimensional profiles of the signals. These 2D profiles are sensitive for a shape of potential and polarizability, even for a strong damping case, and depend on the temperature. This indicates that fifth-order two-dimensional spectroscopy carried out for a different temperature allows us to access information of the potential and the polarizability. We have also presented the Fokker-Planck equation for multi-state systems and applied to the displaced Morse oscillators system. Optical Stark effects of it was observed and discussed. Less