本文主要研究了一个特殊非对称量子阱中的二阶非线性光学极化率 ,并且利用量子力学中的密度矩阵算符理论和迭代方法导出了二次谐波极化率的解析表达式 .最后 ,以典型的 Ga As/ Al Ga As非对称量子阱为例作了数值计算 .数值结果表明 ,较...本文主要研究了一个特殊非对称量子阱中的二阶非线性光学极化率 ,并且利用量子力学中的密度矩阵算符理论和迭代方法导出了二次谐波极化率的解析表达式 .最后 ,以典型的 Ga As/ Al Ga As非对称量子阱为例作了数值计算 .数值结果表明 ,较大的二次谐波极化率与系统的非对称性有关 ,系统的非对称性越大 。展开更多
We demonstrate experimentally the population inversion between 7S1/2 and 6P3/2 levels of cesium in thermal cesium cell with a 455.5 nm pumping laser.We calculate the relative population probabilities at each level the...We demonstrate experimentally the population inversion between 7S1/2 and 6P3/2 levels of cesium in thermal cesium cell with a 455.5 nm pumping laser.We calculate the relative population probabilities at each level theoretically with the density matrix method.In a steady state,5.8% atoms are at 7S1/2 level and 2.9% at 6P3/2 level,which builds up the population inversion between the two levels.We obtain the fluorescence spectra produced in thermal cesium cell in our experiment.The measured relative intensity of each available fluorescence spectral line in the experiment agrees very well with the theoretical result.The demonstrated population inversion between 7S1/2 and 6P3/2 levels can be used to construct an active optical clock of four-level system with a wavelength of 1469.9 nm.展开更多
基金Natural Science Foundation of Guangdong Province and Guangzhou Committee of Science and Technology
文摘本文主要研究了一个特殊非对称量子阱中的二阶非线性光学极化率 ,并且利用量子力学中的密度矩阵算符理论和迭代方法导出了二次谐波极化率的解析表达式 .最后 ,以典型的 Ga As/ Al Ga As非对称量子阱为例作了数值计算 .数值结果表明 ,较大的二次谐波极化率与系统的非对称性有关 ,系统的非对称性越大 。
基金jointly supported by the NNSF of China(60906042 and 61178003)the Yangchen Scholar Project(10B010D)+1 种基金the STPAA(10B001)of Guangzhou City,STP of Panyu Region(2010-D-09-1103004)Project of Academic Innovation Group of Guangzhou City(13C17)
基金supported by the National Natural Science Foundation of China (Grant Nos. 10874009 and 11074011)
文摘We demonstrate experimentally the population inversion between 7S1/2 and 6P3/2 levels of cesium in thermal cesium cell with a 455.5 nm pumping laser.We calculate the relative population probabilities at each level theoretically with the density matrix method.In a steady state,5.8% atoms are at 7S1/2 level and 2.9% at 6P3/2 level,which builds up the population inversion between the two levels.We obtain the fluorescence spectra produced in thermal cesium cell in our experiment.The measured relative intensity of each available fluorescence spectral line in the experiment agrees very well with the theoretical result.The demonstrated population inversion between 7S1/2 and 6P3/2 levels can be used to construct an active optical clock of four-level system with a wavelength of 1469.9 nm.