The effect of the laser polarization direction on the detached electron flux of H− in external field near surface

2017 ◽  
Vol 95 (1) ◽  
pp. 38-43
Author(s):  
T.T. Tang ◽  
Z.L. Zhu ◽  
J.G. Yao ◽  
D.H. Wang
Keyword(s):  
External Field ◽  
Flux Distribution ◽  
Electron Flux ◽  
Azimuth Angle ◽  
Negative Ion ◽  
Polarization Angle ◽  
Laser Polarization ◽  
Polarization Direction ◽  
Near Surface ◽  
Open Orbit

By using the semi-classical open orbit theory, the effect of the laser polarization direction on the detached electron flux of H− in electric field near metal surface has been studied. The result suggests that the azimuth angle [Formula: see text] has little effect on the electron flux distribution. We find that the influence of polarization angle θL on electron flux distribution is more obvious than the influence of the azimuth angle [Formula: see text]. In other words, the effect of the polarization angle θL on electron flux distribution is more important. We hope that our study will provide a new understanding of the electron flux distribution of negative ion in external field and surfaces, and can be used to guide the future experiment research on the negative ion photo-detachment microscopy.

scholarly journals Observation of HClO3 and HClO4 in the Arctic atmosphere

2020 ◽  
Author(s):  
Yee Jun Tham ◽  
Nina Sarnela ◽  
Carlos A. Cuevas ◽  
Iyer Siddharth ◽  
Lisa Beck ◽  
...  
Keyword(s):  
Gas Phase ◽  
Ozone Depletion ◽  
Surface Ozone ◽  
Negative Ion ◽  
The Arctic ◽  
Research Station ◽  
Visible Absorption ◽  
Data Set ◽  
Near Surface ◽  
Arctic Atmosphere

<p>Atmospheric halogens chemistry like the catalytic reaction of bromine and chlorine radicals with ozone (O<sub>3</sub>) has been known to cause the springtime surface-ozone destruction in the polar region. Although the initial atmospheric reactions of chlorine with ozone are well understood, the final oxidation steps leading to the formation of chlorate (ClO<sub>3</sub><sup>-</sup>) and perchlorate (ClO<sub>4</sub><sup>-</sup>) remain unclear due to the lack of direct evidence of their presence and fate in the atmosphere. In this study, we present the first high-resolution ambient data set of gas-phase HClO<sub>3</sub> (chloric acid) and HClO<sub>4</sub> (perchlorate acid) obtained from the field measurement at the Villum Research Station, Station Nord, in high arctic North Greenland (81°36’ N, 16°40’ W) during the spring of 2015. A state-of-the-art chemical ionization atmospheric pressure interface time-of-flight mass spectrometer (CI-APi-TOF) was used in negative ion mode with nitrate ion as the reagent ion to detect the gas-phase HClO<sub>3</sub> and HClO<sub>4</sub>. We measured significant level of HClO<sub>3</sub> and HClO<sub>4</sub> only during the springtime ozone depletion events in the Greenland, with concentration up to 9x10<sup>5</sup> molecule cm<sup>-3</sup>. Air mass trajectory analysis shows that the air during the ozone depletion event was confined to near-surface, indicating that the O<sub>3</sub> and surface of sea-ice/snowpack may play important roles in the formation of HClO<sub>3</sub> and HClO<sub>4</sub>. We used high-level quantum-chemical methods to calculate the ultraviolet-visible absorption spectra and cross-section of HClO<sub>3</sub> and HClO<sub>4</sub> in the gas-phase to assess their fates in the atmosphere. Overall, our results reveal the presence of HClO<sub>3</sub> and HClO<sub>4</sub> during ozone depletion events, which could affect the chlorine chemistry in the Arctic atmosphere.</p>

THE INVESTIGATION OF NON-OSCILLATING STRUCTURE OF THE PHOTODETACHMENT CROSS SECTION OF MOLECULAR ANION USING TRADITIONAL THEORETICAL IMAGING METHOD

2013 ◽  
Vol 12 (05) ◽  
pp. 1350041 ◽  
Author(s):  
MUHAMMAD HANEEF ◽  
SUNEELA ARIF ◽  
JEHAN AKBAR ◽  
NASRULLAH SHAH ◽  
MUHAMMAD ZAHIR
Keyword(s):  
Cross Section ◽  
Electron Flux ◽  
Imaging Method ◽  
Laser Polarization ◽  
Molecular Anion ◽  
Elastic Surface ◽  
Surface Distance ◽  
Soft Surface ◽  
Photodetachment Cross Section ◽  
Analytical Expressions

Using traditional theoretical imaging method, we predict invisible oscillations in the photodetachment cross section of [Formula: see text] near a thin soft surface. A laser which is polarized parallel to the surface is used to knock off electron from [Formula: see text]. Analytical expressions are derived for detached electron flux and photodetachment cross section. The results depend on the inter ion surface distance and separation of the atomic centers of the molecular anion. It is found that the surface strongly affects the detached electron flux and the photodetachment cross section. Unlike the detached electron flux the cross section displays non-oscillating structure. The non-oscillating structure is attributed to the parallel orientation of the laser polarization direction with the thin elastic surface.

The impact of laser polarization direction on local dose rate effects simulation for modern integrated circuits

2015 ◽  
Vol 44 (1) ◽  
pp. 22-26 ◽  
Author(s):  
P. K. Skorobogatov ◽  
A. V. Sogoyan ◽  
G. G. Davydov ◽  
A. N. Egorov ◽  
D. V. Savchenkov
Keyword(s):  
Integrated Circuits ◽  
Dose Rate ◽  
Laser Polarization ◽  
Polarization Direction ◽  
Dose Rate Effects ◽  
Rate Effects ◽  
The Impact

[001] Surface Structure in SrTiO3 — Atomistic Study

1998 ◽  
Vol 05 (01) ◽  
pp. 341-345 ◽  
Author(s):  
Eugene Heifets ◽  
Simon Dorfman ◽  
David Fuks ◽  
Eugene Kotomin ◽  
Alex Gordon
Keyword(s):  
Dipole Moment ◽  
External Field ◽  
Polarization Effect ◽  
Surface Region ◽  
Superconducting Films ◽  
Surface Layers ◽  
Near Surface ◽  
Atomistic Study ◽  
Model Technique ◽  
Thin Superconducting Films

Thin superconducting films attract great attention as a promising material for plenty of applications. The surface determines most of the physical properties of these films. We studied the polarization effect for the [001] surface of perovskite ABO 3 superconducting crystals on the example of SrTiO 3. Optimization of the ion positions in several surface layers is provided. These ions are placed in the external field of the rest crystal. The interaction between ions is described by means of the shell model technique. We show that Ti +4, Sr 2+ and O -2 ions displace differently from their crystalline sites, which leads to the creation of a dipole moment in the near-surface region.

Photodetached electron spectrum of H- near a surface having spherical dent

2015 ◽  
Vol 14 (08) ◽  
pp. 1550063 ◽  
Author(s):  
Muhammad Haneef ◽  
Bakhtawar ◽  
Suneela Arif ◽  
Jehan Akbar ◽  
Nasrullah Shah
Keyword(s):  
Cross Section ◽  
Electron Flux ◽  
Focal Length ◽  
Negative Ions ◽  
Negative Ion ◽  
Concave Surface ◽  
Radius Of Curvature ◽  
Imaging Method ◽  
Surface Distance ◽  
Photodetachment Cross Section

The detached electron flux and photodetachment cross section are derived using the theoretical imaging method and quantum approach for system comprising of hydrogen negative ion ([Formula: see text]) placed near a surface having spherical dent. The dent is modeled like a spherical concave surface. It is observed that the spherical dent generates additional oscillatory and smooth structure in the detached electron flux and photodetachment cross section, respectively. The radius of curvature, inter-ion surface distance and the dent factor strongly manipulate the results. When the inter-ion surface distance is equal to the focal length of the concave surface, the detached electron flux and photodetachment cross section are not well behaved. The photodetachment cross section is also not well behaved for the inter-ion surface distance equal to the radius of curvature. The focus and center of curvature of the concave surface act as a spherical singularity. This study gives new understanding on the photodetachment of negative ions in the vicinity of concave surfaces.

Absolute measurement of three-dimensional polarization direction using scanning nonlinear dielectric Microscopy

2004 ◽  
Vol 838 ◽  
Author(s):  
Yasuo Cho ◽  
Tomoyuki Sugihara ◽  
Hiroyuki Odagawa
Keyword(s):  
Three Dimensional ◽  
Absolute Measurement ◽  
Polarization Angle ◽  
Polarization Direction ◽  
Periodically Poled ◽  
Nonlinear Dielectric ◽  
Periodically Poled Lithium Niobate ◽  
Measured Polarization ◽  
The Absolute ◽  
Microdomain Structure

ABSTRACTA technique for measuring the absolute value of the ferroelectric polarization angle using scanning nonlinear dielectric microscopy (SNDM) is proposed and demonstrated. Using the technique, periodically poled lithium niobate (PPLN) with three-dimensional domain structure is observed. The measured polarization angles agreed well with the actual polarization orientations, and allowed precise visualization of the microdomain structure in PPLN. Through this experiment, we confirmed that SNDM is a useful tool for the absolute evaluation of the three-dimensional polarization direction.

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