We theoretically investigate the Autler-Townes （AT） splitting in the photoelectron spectra of three-level ladder K2 molecule driven by a pump-probe pulse via employing the time- dependent wave packet approach. The d...We theoretically investigate the Autler-Townes （AT） splitting in the photoelectron spectra of three-level ladder K2 molecule driven by a pump-probe pulse via employing the time- dependent wave packet approach. The dependence of AT splitting on two laser intensities and wavelengths are studied in detail. We firstly quantify these effects on peak shift and AT separation. The photoelectron spectra show double splitting with symmetric profiles, but with asymmetric profiles when the wavelength is changed. The magnitude of AT splitting increases with the pump laser intensity, but does not vary with probe intensity. The shifts of the absorption peaks and the splitting between AT doublet are predicted by using an analyt- ical fitting function when the intensity/wavelength of one of the two fields is changed. These novel results are of importance for the molecular spectroscopy and may further stimulate the first principles theoretical studies analytically.展开更多
利用PPG-1脉冲电流源(400 k A,100 ns),同时驱动X-pinch和双丝Z箍缩负载.用X-pinch作为X射线源,对双丝Z箍缩进行了轴向背光照相的初步实验.得到了双丝Z箍缩在r-θ平面上随时间演化的图像,观察到了丝阵Z箍缩所有早期过程,包括丝芯膨胀、...利用PPG-1脉冲电流源(400 k A,100 ns),同时驱动X-pinch和双丝Z箍缩负载.用X-pinch作为X射线源,对双丝Z箍缩进行了轴向背光照相的初步实验.得到了双丝Z箍缩在r-θ平面上随时间演化的图像,观察到了丝阵Z箍缩所有早期过程,包括丝芯膨胀、冕层等离子体产生、等离子体向丝阵中心的运动、先驱等离子体形成.利用阶跃光楔滤片,对上述背光图像进行了等离子体质量面密度的标定,首次得到了在r-θ平面上双丝Z箍缩等离子体质量面密度的时空分布图像.展开更多
Silica-based fiber tips are used in a variety of spectroscopic, micro- or nano-scopic optical sensor applications and photonic micro-devices. The miniaturization of optical sensor systems and the technical implementat...Silica-based fiber tips are used in a variety of spectroscopic, micro- or nano-scopic optical sensor applications and photonic micro-devices. The miniaturization of optical sensor systems and the technical implementation using optical fibers can provide new sensor designs with improved properties and functionality for new applications. The selective-etching of specifically doped silica fibers is a promising method in order to form complex photonic micro structures at the end or within fibers such as tips and cavities in various shapes useful for the all-fiber sensor and imaging applications. In the present study, we investigated the preparation of geometrically predefined, nanoscaled fiber tips by taking advantage of the dopant concentration profiles of highly doped step-index fibers. For this purpose, a gas phase etching process using hydrofluoric acid （HF） vapor was applied. The shaping of the fiber tips was based on very different etching rates as a result of the doping characteristics of specific optical fibers. Technological studies on the influence of the etching gas atmosphere on the temporal tip shaping and the final geometry were performed using undoped and doped silica fibers. The influence of the doping characteristics was investigated in phosphorus-, germanium-, fluorine- and boron-doped glass fibers. Narrow exposed as well as protected internal fiber tips in various shapes and tip radiuses down to less than 15 nm were achieved and characterized geometrically and topologically. For investigations into surface plasmon resonance effects, the fiber tips were coated with nanometer-sized silver layers by means of vapour deposition and finally subjected to an annealing treatment.展开更多
基金The code used in our calculation is provided by Pro- fessor Ke-li Han from Dalian Institute of Chemical Physics, Chinese Academy of Science, and we appreci- ate his help and kind advice. This work was supported by the National Natural Science Foundation of China （No.11447020）, the Natural Science Foundation of Hu- nan province （No.2015JJ3104）, and the Scientific Re- search Foundation for the Returned Overseas Chinese Scholars, State Education Ministry.
文摘We theoretically investigate the Autler-Townes （AT） splitting in the photoelectron spectra of three-level ladder K2 molecule driven by a pump-probe pulse via employing the time- dependent wave packet approach. The dependence of AT splitting on two laser intensities and wavelengths are studied in detail. We firstly quantify these effects on peak shift and AT separation. The photoelectron spectra show double splitting with symmetric profiles, but with asymmetric profiles when the wavelength is changed. The magnitude of AT splitting increases with the pump laser intensity, but does not vary with probe intensity. The shifts of the absorption peaks and the splitting between AT doublet are predicted by using an analyt- ical fitting function when the intensity/wavelength of one of the two fields is changed. These novel results are of importance for the molecular spectroscopy and may further stimulate the first principles theoretical studies analytically.
文摘利用PPG-1脉冲电流源(400 k A,100 ns),同时驱动X-pinch和双丝Z箍缩负载.用X-pinch作为X射线源,对双丝Z箍缩进行了轴向背光照相的初步实验.得到了双丝Z箍缩在r-θ平面上随时间演化的图像,观察到了丝阵Z箍缩所有早期过程,包括丝芯膨胀、冕层等离子体产生、等离子体向丝阵中心的运动、先驱等离子体形成.利用阶跃光楔滤片,对上述背光图像进行了等离子体质量面密度的标定,首次得到了在r-θ平面上双丝Z箍缩等离子体质量面密度的时空分布图像.
文摘Silica-based fiber tips are used in a variety of spectroscopic, micro- or nano-scopic optical sensor applications and photonic micro-devices. The miniaturization of optical sensor systems and the technical implementation using optical fibers can provide new sensor designs with improved properties and functionality for new applications. The selective-etching of specifically doped silica fibers is a promising method in order to form complex photonic micro structures at the end or within fibers such as tips and cavities in various shapes useful for the all-fiber sensor and imaging applications. In the present study, we investigated the preparation of geometrically predefined, nanoscaled fiber tips by taking advantage of the dopant concentration profiles of highly doped step-index fibers. For this purpose, a gas phase etching process using hydrofluoric acid （HF） vapor was applied. The shaping of the fiber tips was based on very different etching rates as a result of the doping characteristics of specific optical fibers. Technological studies on the influence of the etching gas atmosphere on the temporal tip shaping and the final geometry were performed using undoped and doped silica fibers. The influence of the doping characteristics was investigated in phosphorus-, germanium-, fluorine- and boron-doped glass fibers. Narrow exposed as well as protected internal fiber tips in various shapes and tip radiuses down to less than 15 nm were achieved and characterized geometrically and topologically. For investigations into surface plasmon resonance effects, the fiber tips were coated with nanometer-sized silver layers by means of vapour deposition and finally subjected to an annealing treatment.
