Electron spin polarization effects in a study of transient hydrogen atoms in acidic ices under electron irradiation

1974 ◽  
Vol 78 (13) ◽  
pp. 1336-1337 ◽  
Author(s):  
Hirotsugu Shiraishi ◽  
Hajime Kadoi ◽  
Yosuke Katsumura ◽  
Yoneho Tabata ◽  
Keichi Oshima
Keyword(s):  
Spin Polarization ◽  
Electron Spin ◽  
Electron Irradiation ◽  
Electron Spin Polarization ◽  
Hydrogen Atoms ◽  
Polarization Effects ◽  
Spin Polarization Effects

Spin-polarization effects in Cherenkov radiation from electrons

2020 ◽  
Vol 98 (7) ◽  
pp. 660-663
Author(s):  
A.A. Peshkov
Keyword(s):  
Spin Polarization ◽  
Cherenkov Radiation ◽  
Stokes Parameters ◽  
Electron Spin Polarization ◽  
Polarized Electrons ◽  
Small Component ◽  
Polarization Effects ◽  
Spin Polarized ◽  
Linearly Polarized ◽  
Spin Polarization Effects

A quantum electrodynamical theory of Cherenkov radiation emitted by spin-polarized electrons moving in an isotropic medium is developed within the density matrix framework. Special attention is paid to the polarization properties of the emitted photons described by means of Stokes parameters. It is demonstrated that, although the Cherenkov radiation is primarily linearly polarized in the plane containing the direction of observation and the path of the electrons, the photons may have a small component of circular polarization of the order of 3 × 10−6 for electron kinetic energy of 500 keV due to the initial electron spin polarization, whose existence can be confirmed by sensitive measurements in the future.

Effects on the magnetic and optical properties of Co-doped ZnO at different electronic states

2017 ◽  
Vol 31 (31) ◽  
pp. 1750247
Author(s):  
Qingyu Huo ◽  
Zhenchao Xu ◽  
Linfeng Qu
Keyword(s):  
Absorption Spectrum ◽  
Spin Polarization ◽  
Electron Spin ◽  
Magnetic Moments ◽  
The State ◽  
Band Gaps ◽  
Electron Spin Polarization ◽  
Approximation Formula ◽  
Doped Zno ◽  
Co Doped

Both blue and red shifts in the absorption spectrum of Co-doped ZnO have been reported at a similar concentration range of doped Co. Moreover, the sources of magnetism of Co-doped ZnO are controversial. To solve these problems, the geometry optimization and energy of different Co-doped ZnO systems were calculated at the states of electron spin polarization and nonspin polarization by adopting plane-wave ultra-soft pseudopotential technology based on density function theory. At the state of electron nonspin polarization, the total energies increased as the concentration of Co-doped increased. The doped systems also became unstable. The formation energies increased and doping became difficult. Furthermore, the band gaps widened and the absorption spectrum exhibited a blue shift. The band gaps were corrected by local-density approximation + [Formula: see text] at the state of electron spin polarization. The magnetic moments of the doped systems weakened as the concentration of doped Co increased. The magnetic moments were derived from the coupling effects of [Formula: see text]–[Formula: see text]. The band gaps narrowed and the absorption spectrum exhibited a red shift. The inconsistencies of the band gaps and absorption spectrum at the states of electron spin polarization and nonspin polarization were first discovered in this research, and the sources of Co-doped ZnO magnetism were also reinterpreted.

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