Results of theoretical researches of the saturated absorption resonance shape in a method of the probing field on V-type of transitions are represented. It is shown that in case of opposite circulary polarized optical...Results of theoretical researches of the saturated absorption resonance shape in a method of the probing field on V-type of transitions are represented. It is shown that in case of opposite circulary polarized optical fields the resonance is shown in the form of cross, and its form strongly depends on relaxation constants of levels and it can be represented as in the form of a dip, and absorption peak. Thus the peak form has exclusively coherent character. Atomic transitions are offered, on which observation of the given effect is possible.展开更多
We demonstrate an experimental method for the in situ temperature measurement of atomic vapor using the saturated absorption spectrum. By separately manipulating the frequency of the pump and probe beams, the position...We demonstrate an experimental method for the in situ temperature measurement of atomic vapor using the saturated absorption spectrum. By separately manipulating the frequency of the pump and probe beams, the position of the crossover peaks can move along the spectrum. Different velocity classes of atoms contribute to the crossover during the movement. We study the relationship between the intensity change of peaks and vapor temperature. Our experimental result around room temperature shows a deviation of less than 0.3 K. Compared with traditional thermometry using absorption spectroscopy, higher accuracy can theoretically be achieved with real-time thermometry.展开更多
N-doped FZ-Si crystals and N-doped NTD FZ-Si crystals and their annealing behavior have been studied by IR spectrum. Two models of nitrogen configuration, nearly substitutional nitrogen and interstitial nitrogen pair,...N-doped FZ-Si crystals and N-doped NTD FZ-Si crystals and their annealing behavior have been studied by IR spectrum. Two models of nitrogen configuration, nearly substitutional nitrogen and interstitial nitrogen pair, have been proposed and two nitrogen-related IR absorption peaks at 767cm-1 and 963cm-1 have been well explained.展开更多
We investigate the differential cross sections （DCS） of elastic electron scattering from CH4, CF4 and SF6 at six impact energies in a range of 100 700eV by employing the independent atom model （IAM） together with ...We investigate the differential cross sections （DCS） of elastic electron scattering from CH4, CF4 and SF6 at six impact energies in a range of 100 700eV by employing the independent atom model （IAM） together with the relativistic partial waves. The atom is present in an optical potential which is complex, spherically symmetric, and energy dependent. The optical potential of the atom is the sum of the direct static, dynamic polarization, local exchange and modified absorption potentials. The results obtained by using a modified absorption potential show significant improvements on the unmodified absorption potential results. The present results are generally in good agreement with experimental data available. In addition, the present results indicate that the structure of molecule manifests the observable effects on electron- molecule scattering.展开更多
In this paper,Topological Electronegativity Index (TEI) was developed to express the relatively power of an group in a molecule to attract electrons to itself.The charge effect,the relaxation effect and the electrosta...In this paper,Topological Electronegativity Index (TEI) was developed to express the relatively power of an group in a molecule to attract electrons to itself.The charge effect,the relaxation effect and the electrostatic field effect on the C 1s core ionization energies of saturated molecules were evaluated,based on the topological electronegativity index TEI,the atomic electronegativity χP and the polarizability α.The charge effect was scaled by the topological electronegativity index discrepancy between the C and X (X is atom or group) in the C-X bond.The relaxation effect (induced dipole) was scaled by the charge on the ionized carbon atom together with the polarizabiliy of the X.The electrostatic field effect was scaled by the charges on the atoms attached directly to the ionized carbon atom.Further,the shielding effect ΔSi of the C 1s electron in the saturated molecules was expressed by the charge effect and the relaxation effect together with the electrostatic field effect.By introducing the ΔSi into the Slater model,a Slater-like model was obtained for calculating the C 1s core ionization energy E1,C of saturated molecules,whose correlation coefficient r is 0.99943 and the average absolute error between the calculated and the experimental C 1s core ionization energies is only 0.094eV for 81 saturated molecules.Also the cross-correlation was tested by the leave-one-out (LOO) cross-validation method,and the obtained model has good predictive ability and stability (the correlation coefficient rcv is 0.99928,the average absolute error between the predicted and the experimental values is only 0.105 eV).展开更多
文摘Results of theoretical researches of the saturated absorption resonance shape in a method of the probing field on V-type of transitions are represented. It is shown that in case of opposite circulary polarized optical fields the resonance is shown in the form of cross, and its form strongly depends on relaxation constants of levels and it can be represented as in the form of a dip, and absorption peak. Thus the peak form has exclusively coherent character. Atomic transitions are offered, on which observation of the given effect is possible.
基金supported by the National Natural Science Foundation of China (Grant No. 61703025)。
文摘We demonstrate an experimental method for the in situ temperature measurement of atomic vapor using the saturated absorption spectrum. By separately manipulating the frequency of the pump and probe beams, the position of the crossover peaks can move along the spectrum. Different velocity classes of atoms contribute to the crossover during the movement. We study the relationship between the intensity change of peaks and vapor temperature. Our experimental result around room temperature shows a deviation of less than 0.3 K. Compared with traditional thermometry using absorption spectroscopy, higher accuracy can theoretically be achieved with real-time thermometry.
文摘N-doped FZ-Si crystals and N-doped NTD FZ-Si crystals and their annealing behavior have been studied by IR spectrum. Two models of nitrogen configuration, nearly substitutional nitrogen and interstitial nitrogen pair, have been proposed and two nitrogen-related IR absorption peaks at 767cm-1 and 963cm-1 have been well explained.
基金Project supported by the Shanghai Development Foundation from Science and Technology, China （Grant Nos 06JC14082 and 06QA14062）, the National Natural Science Foundation of China （Grant No 10535010）, and the Knowledge Innovation Project of Chinese Academy of Sciences （Grant No KJXC3-SYW-N2）.
文摘We investigate the differential cross sections （DCS） of elastic electron scattering from CH4, CF4 and SF6 at six impact energies in a range of 100 700eV by employing the independent atom model （IAM） together with the relativistic partial waves. The atom is present in an optical potential which is complex, spherically symmetric, and energy dependent. The optical potential of the atom is the sum of the direct static, dynamic polarization, local exchange and modified absorption potentials. The results obtained by using a modified absorption potential show significant improvements on the unmodified absorption potential results. The present results are generally in good agreement with experimental data available. In addition, the present results indicate that the structure of molecule manifests the observable effects on electron- molecule scattering.
文摘In this paper,Topological Electronegativity Index (TEI) was developed to express the relatively power of an group in a molecule to attract electrons to itself.The charge effect,the relaxation effect and the electrostatic field effect on the C 1s core ionization energies of saturated molecules were evaluated,based on the topological electronegativity index TEI,the atomic electronegativity χP and the polarizability α.The charge effect was scaled by the topological electronegativity index discrepancy between the C and X (X is atom or group) in the C-X bond.The relaxation effect (induced dipole) was scaled by the charge on the ionized carbon atom together with the polarizabiliy of the X.The electrostatic field effect was scaled by the charges on the atoms attached directly to the ionized carbon atom.Further,the shielding effect ΔSi of the C 1s electron in the saturated molecules was expressed by the charge effect and the relaxation effect together with the electrostatic field effect.By introducing the ΔSi into the Slater model,a Slater-like model was obtained for calculating the C 1s core ionization energy E1,C of saturated molecules,whose correlation coefficient r is 0.99943 and the average absolute error between the calculated and the experimental C 1s core ionization energies is only 0.094eV for 81 saturated molecules.Also the cross-correlation was tested by the leave-one-out (LOO) cross-validation method,and the obtained model has good predictive ability and stability (the correlation coefficient rcv is 0.99928,the average absolute error between the predicted and the experimental values is only 0.105 eV).
