Free migration of vacancies in niobium at 250 K

Irradiation-Induced Site Change of Hydrogen in Niobium

“…8) It was attributed to free migration of monovacancies. 9) This interpretation was supported by perturbed angular correlation 10) and positron-lifetime experiments. 11) It was observed by electrical resistivity measurements 12) and positron-lifetime measurements 11) that, on hydrogen doping, this stage was shifted by about 100 -160 K to higher temperature.…”

Perturbed Angular Correlation Spectroscopy – A Tool for the Study of Defects and Diffusion at the Atomic Scale

“…These are summarized in Table 2, arranged by the type of material and the general physical phenomenon considered. [60] • In in Zr 2 Rh [61] • In in HfAl 2 & ZrAl 2 [62] • In in Pd 3 Ga 7 [65] • In in Ni 2 Al 3 & related [66] • In in (Hf/Zr) 3 Al 2 & (Hf/Zr) 4 Al 3 [68] • In & Hf in bixbyites [63,64,67] • Hf in LiNbO 3 & LiTaO 3 [72] Probe:defect complex configurations [26] • Cd:acceptor and Cd:V Te charge states in CdTe [71] • Cd:vacancy in II-VI compounds [13] • Cd:acceptor in III-Vs, Si, and Ge [11,85,86] • In:V O in CeO 2 [69] • In:V O in CoO [70] • In:V O in CeO 2 [87] Probe:defect interactions • In:V Ni in NiAl [73] • In:V Fe in FeAl [26] • In:V Sm in SmNi 2 [75] • Probe:solute pairs in metals [4] • In:vacancy pairs in metals [9,[78][79][80][81] • In:V Cd in CdTe [74] • In:V Cd in CdS [76] • Pd:V Si in Si [77] • Cd:H in III-V compounds [11] • Cd:acceptors in Si & Ge [11] • Cd:V O in ZrO 2 [112] Atomic jumps • H near Hf in Y [94], Hf [95], & DyH 2±δ [96] • H near Cd in HfV 2 H x [98] • V R near Cd in R 1-x Ni 2 [75] • Cd in β-Mn ...…”

“…Observed PAC signals exhibit significant inhomogeneous broadening in such cases. Depending on the material and on the probe, the observed PAC signals could be broadened signals that arise from probes without defects in the first or second neighbor shell, as was the case for indium implanted in ZnO [88], in GaP [89], and in Nb [90], or that arise from probes with defects in the first or second neighbor shell, as was the case for Pd in Nb [90].…”

“…For example, this was used to analyze the formation and the dissociation of indium/cadmium-vacancy pairs in CdS [76]. A variation of this method, in which the excess vacancies were residuals of the radiation damage resulting from implantation of probes or from irradiation of samples rather than those frozen in after a quench from high temperature, was used to study association and disassociation of Pd-vacancy pairs in Si [77] and of In-vacancy complexes in fcc metals [4] and bcc metals [78,79,80,81]. For the studies involving Si and the metals, vacancy concentrations were not constant so that Eq.…”

Investigation of Electronic States of Pd in 4H-SiC by Means of Radiotracer-DLTS

“…The radioactive isotopes necessary for our radiotracer investigations were incorporated in the SiC crystals by recoil implantation at the ISL of the Hahn-Meitner-Institut in Berlin [4]. For the implantation of the radioactive isotope 100 Pd, a 90 MeV 12 C primary beam was lead on a 93 Nb target foil (1.5 mg/cm 2 ) causing the nuclear reaction 93 Nb ( 12 C, 5n) 100 Ag → 100 Pd [5]. Due to the recoil the reaction products are kicked out of the target foil and are implanted into the SiC samples mounted off-axis the primary beam with a maximal recoil energy of about 10 MeV with a broad distribution to lower energies.…”