Results 41 to 50 of about 9,908 (221)
Analysis of electron-positron momentum spectra of metallic alloys as supported by first-principles calculations [PDF]
, 2007 Electron-positron momentum distributions measured by the coincidence Doppler broadening method can be used in the chemical analysis of the annihilation environment, typically a vacancy-impurity complex in a solid.
A. Dupasquier +14 more
core +2 more sources
Optical Materials: X, 2022 Gamma-ray-induced positron annihilation lifetime spectroscopy (GiPALS) was used to characterize pristine and codoped Lu3Al5O12 (LuAG) crystals grown using Czochralski (Cz) and micropulling-down (mPD) methods.
Mamoru Kitaura +2 more
doaj +1 more source
Single-shot positron annihilation lifetime spectroscopy with LYSO scintillators [PDF]
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2016 We have evaluated the application of a lutetium yttrium oxyorthosilicate (LYSO) based detector to single-shot positron annihilation lifetime spectroscopy. We compare this detector directly with a similarly configured PbWO4 scintillator, which is the usual choice for such measurements. We find that the signal to noise ratio obtained using LYSO is around
Alonso, A. M. +3 more
openaire +3 more sources
Selective Production of Rydberg-Stark States of Positronium [PDF]
, 2015 Rydberg positronium (Ps) atoms have been prepared in selected Stark states via two-step (1s→2p→nd/ns) optical excitation. Two methods have been used to achieve Stark-state selection: a field ionization filter that transmits the outermost states with ...
Alonso, AM +5 more
core +2 more sources
Nanocrystalline aluminum studied by positron annihilation lifetime spectroscopy
Acta Physica Sinica, 2014 Aluminum nanoparticles with an average diameter of about 48 nm are compressed in a cemented-carbide mold under different pressures to produce nanocrystalline aluminum by the hot-pressing technology in a high vacuum condition. The X-ray diffraction and the positron annihilation lifetime spectroscopy (PALS) are used to characterize the microscopic ...
null Li Yu +6 more
openaire +1 more source
A study of vacancy defects related to gray tracks in KTiOPO4 (KTP) using positron annihilation
AIP Advances, 2014 For the first time to our knowledge, positron annihilation spectroscopy (PAS) was used to study vacancy defects in KTiOPO4 (KTP) single crystals. Positron annihilation lifetime spectroscopy combined with dielectric measurements identified the existence ...
Yang Zhang +5 more
doaj +1 more source
Surfaces of colloidal PbSe nanocrystals probed by thin-film positron annihilation spectroscopy
APL Materials, 2013 Positron annihilation lifetime spectroscopy and positron-electron momentum density (PEMD) studies on multilayers of PbSe nanocrystals (NCs), supported by transmission electron microscopy, show that positrons are strongly trapped at NC surfaces, where ...
L. Chai +13 more
doaj +1 more source
Microscopic identification of native donor Ga-vacancy complexes in Te-doped GaAs [PDF]
, 1999 Native vacancies in Te-doped (5×1016–5×1018cm−3) GaAs were investigated by means of positron lifetime and Doppler-broadening coincidence spectroscopy.
Gebauer, J. +5 more
core +1 more source
Structural Defects in TiNi-Based Alloys after Warm ECAP
Metals, 2020 The microstructure, martensitic transformations and crystal structure defects in the Ti50Ni47.3Fe2.7 (at%) alloy after equal-channel angular pressing (ECAP, angle 90°, route BC, 1–3 passes at T = 723 K) have been investigated.
Aleksandr Lotkov +4 more
doaj +1 more source