Analyzing the photodetachment cross section ofH−in electric and magnetic fields with arbitrary orientation

The photodetachment of the H– ion in perpendicular electric and magnetic fields near a metal surface has been investigated on the basis of the semiclassical closed-orbit theory. Firstly, we give a clear physical picture of the detached electron’s movement and find out the closed orbits of this system. Then we put forward an analytical formula for calculating the photodetachment cross section. It is found that the perpendicular electric and magnetic fields can produce some interesting effects. As the magnetic field is relatively weak, the influence of the electric field and the electrostatic potential dominates and the oscillatory structure in the photodetachment cross section exhibits a smoothly oscillating curve. As we keep the electric field and the ion–surface distance unchanged, with the increase of the magnetic field strength, the number of closed orbits is increased and the oscillatory structure in the photodetachment cross section is characterized by broad Landau level envelops. Therefore, we can use the perpendicular electric and magnetic fields to control the photodetachment of H– near a metal surface. Our study may guide future experimental research on the photodetachment microscopy of negative ion in external fields near surfaces.

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An attempt to detect some electro-optical effects

Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character ◽

10.1098/rspa.1909.0029 ◽

1909 ◽

Vol 82 (553) ◽

pp. 224-226

Keyword(s):

Magnetic Fields ◽

Cross Section ◽

Simple Form ◽

Silver Film ◽

Short Account ◽

Optical Part ◽

Propagation Of Light ◽

Optical Effects ◽

Electric And Magnetic Fields ◽

Velocity Of Propagation

The following paper contains a description of some experiments made with the object of detecting possible effects due to electric and magnetic fields and moving matter on the velocity of propagation of light in glass. The results obtained were negative, but it seems worth while to publish a short account of the experiments. The optical part of the apparatus is a simple form of interferometer which proved very easy and convenient to work with. It consists of a square glass frame made up of glass bars of square cross-section cemented together with canada balsam. Three of the corners are cut off at 45°, as shown in the figure, and the fourth corner contains a half silvered surface FF. Light entering in the direction of the arrow A is divided into two beams by the silver film, which pass round the frame in opposite directions, being totally reflected at the cut-off corners. Half of each beam emerges in the direction of the arrow B, and the two beams at B are in a condition to interfere with each other.

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Resonant Light Absorption by Semiconductor Quantum Dots

Advances in Condensed Matter Physics ◽

10.1155/2009/654190 ◽

2009 ◽

Vol 2009 ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

I. G. Lang ◽

S. T. Pavlov

Keyword(s):

Quantum Dots ◽

Magnetic Fields ◽

Cross Section ◽

Light Absorption ◽

Semiconductor Quantum Dots ◽

Electric And Magnetic Fields ◽

The Cross

The cross-section of light absorption by size-quantized semiconductor quantum dots (QD) is calculated in the case of a resonance with an exciton in cubical crystals of class. The interference of stimulating and induced electric and magnetic fields is taken into account. The cross-section of light absorption is proportional to the exciton nonradiative damping .

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