Polymer Nanocomposites with Silver Nanoparticles Formed by Low-Energy Ion Implantation: Slow Positron Beam Spectroscopy Studies

ABSTRACTVacancy-type defects in ion implanted Si were studied by a monoenergetic positron beam. The depth-distributions of the defects were obtained from measurements of Doppler broadening profiles of the positron annihilation as a function of incident positron energy. The results showed that a size of vacany-clusters introduced by 150-keV P+-ion implantation was found to be smaller than that introduced by 2-MeV P+-ion implantation. This was attributed to an overlap of collision cascades in low-energy (150 keV) ion implanted specimens. From isochronal annealing experiments for 80-keV B+- and 150-keV P+-ion implanted specimens, the defected region was removed by 1200 °C annealing, however, for 2-MeV P+-implanted specimen, two-types of oxygen-vacancy complexes were found to coexist even after 1200 °C annealing.

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Zirconium-ion implantation of zircaloy-4 investiged by slow positron beam

Acta Physica Sinica ◽

10.7498/aps.56.6543 ◽

2007 ◽

Vol 56 (11) ◽

pp. 6543

Author(s):

Hao Xiao-Peng ◽

Wang Bao-Yi ◽

Yu Run-Sheng ◽

Wei Long

Keyword(s):

Ion Implantation ◽

Positron Beam ◽

Slow Positron

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Present status of the low energy linac-based slow positron beam and positronium spectrometer in Saclay

Journal of Physics Conference Series ◽

10.1088/1742-6596/505/1/012036 ◽

2014 ◽

Vol 505 ◽

pp. 012036 ◽

Cited By ~ 4

Author(s):

L Liszkay ◽

P Comini ◽

C Corbel ◽

P Debu ◽

P Grandemange ◽

...

Keyword(s):

Present Status ◽

Positron Beam ◽

Low Energy ◽

Slow Positron

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Ion-Implantation Induced Defects in ZnO Studied by a Slow Positron Beam

Materials Science Forum ◽

10.4028/www.scientific.net/msf.445-446.57 ◽

2004 ◽

Vol 445-446 ◽

pp. 57-59 ◽

Cited By ~ 3

Author(s):

Z.Q. Chen ◽

Masaki Maekawa ◽

Takashi Sekiguchi ◽

Ryoichi Suzuki ◽

Atsuo Kawasuso

Keyword(s):

Ion Implantation ◽

Positron Beam ◽

Slow Positron ◽

Induced Defects

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Design and Simulation of a Trap-Based Pulsed Slow Positron Beam

Materials Science Forum ◽

10.4028/www.scientific.net/msf.733.314 ◽

2012 ◽

Vol 733 ◽

pp. 314-317 ◽

Cited By ~ 2

Author(s):

Chun Qing He ◽

Jun Cheng Wang ◽

Jun Zhu ◽

Shao Jie Wang

Keyword(s):

Time Resolution ◽

Pulse Width ◽

Lower Energy ◽

Drift Tube ◽

Penning Trap ◽

Positron Beam ◽

Low Energy ◽

Energy Dispersion ◽

Slow Positron ◽

Wave Generator

A simple pulsed slow positron beam based on a Penning-trap has been designed and is being constructed in Wuhan University. The cooled positrons from the trap with very low energy dispersion are dumped and chopped to pulses of a few tens of ns in width. Positron pulses are bunched by adjusting the potential of drift tube using an arbitrary wave generator, then accelerated to the target. Influences of the pulse width, the energy dispersion of positrons etc. on the time resolution of bunched positron pulse are simulated. The result shows that lower energy dispersion of positrons leads to much narrower positron pulses, indicating that a trap-based slow positron beam has a great advantage in developing a pulsed slow positron beam.

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Synthesis of porous silicon with silver nanoparticles by low-energy ion implantation

Russian Microelectronics ◽

10.1134/s1063739715080028 ◽

2015 ◽

Vol 44 (8) ◽

pp. 546-551 ◽

Cited By ~ 2

Author(s):

R. I. Batalov ◽

V. F. Valeev ◽

V. I. Nuzhdin ◽

V. V. Vorebev ◽

Yu. N. Osin ◽

...

Keyword(s):

Silver Nanoparticles ◽

Porous Silicon ◽

Ion Implantation ◽

Low Energy

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Slow positron beam at the JINR, Dubna

Nukleonika ◽

10.1515/nuka-2015-0130 ◽

2015 ◽

Vol 60 (4) ◽

pp. 725-728 ◽

Cited By ~ 10

Author(s):

Paweł Horodek ◽

Andrey G. Kobets ◽

Igor N. Meshkov ◽

Alexey A. Sidorin ◽

Oleg S. Orlov

Keyword(s):

Diffusion Length ◽

Nuclear Research ◽

Positron Beam ◽

Positron Annihilation Spectroscopy ◽

Low Energy ◽

Positron Energy ◽

Slow Positron ◽

Tungsten Foil ◽

Sample Chamber ◽

Variable Energy

Abstract The Low Energy Positron Toroidal Accumulator (LEPTA) at the Joint Institute for Nuclear Research (JINR) proposed for generation of positronium in flight has been adopted for positron annihilation spectroscopy (PAS). The positron injector generates continuous slow positron beam with positron energy range between 50 eV and 35 keV. The radioactive 22Na isotope is used. In distinction to popular tungsten foil, here the solid neon is used as moderator. It allows to obtain the beam intensity of about 105 e+/s width energy spectrum characterized by full width at half maximum (FWHM) of 3.4 eV and a tail to lower energies of about 30 eV. The paper covers the characteristic of variable energy positron beam at the LEPTA facility: parameters, the rule of moderation, scheme of injector, and transportation of positrons into the sample chamber. Recent status of the project and its development in the field of PAS is discussed. As an example, the measurement of the positron diffusion length in pure iron is demonstrated.

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