Effect of doping with rare-earth elements (Eu, Tb, Dy) on the conductivity of Bi2Te3 layered single crystals

Thermoelectric properties and phase transition of doped single crystals and polycrystals of Bi2Te3

“…Pyrolysis of polycarbosilane polyme by Key et al 43 anomalies associated with phase transition in the ρ(T) dependence of the Bi 2 Te 3 +1%CuI single crystal (Figure 5B) will be discussed later. The observed anisotropy of the electrical resistivity ⊥ (T)/ ‖ (T) ∼ 10 (where ‖ (T) is the resistivity along the crystal growth axis, and ⊥ (T) is the resistivity across the crystal growth axis) corresponds to data from the literature [32][33][34][35][36] and is consistent with the presence of quasi-two-dimensional electron transport. For resistivity ‖ (T), the anomaly was not observed; similarly, such anomalies were absent in the literature data for measuring single crystals along a well-conducting plane.…”

“…29,30 The physics of resin flow into a mold under pressure is similar to the seepage problem and so similar approaches have been used also to model the flow of resin into a mold containing fiber mats. 23,[31][32][33][34][35][36][37][38] The models are used in these cases to determine the resin flow front and mold filling times corresponding to different infiltration conditions.…”

“…29,30 The physics of resin under pressure is similar to the seepage pr lar approaches have been used also to mod into a mold containing fiber mats. 23,[31][32][33][34][35][36][37][38] T in these cases to determine the resin flow ing times corresponding to different infilt Preceramic polycarbosilane polymers as precursors to make ceramic fibers 10,3 trix. [7][8][9]40,41 The chemical and volume ch pany ceramization of the polymer during documented in several studies.…”

“…6,7, Bismuth telluride exhibits a layered structure 29 and anisotropy in terms of electron transport properties. [32][33][34][35][36] In a previous study, 38 fivefold layers in Bi 2 Te 3 with a strong Bi-Te bond and a weak van der Waals Te-Te bond were mechanically exfoliated by dissociating the van der Waals Te-Te bonds. This enables a single layer or several layers to be obtained.…”

Incorporation of Europium in Bi2Te3 Topological Insulator Epitaxial Films

“…The measurements were conducted at T = 5 K. The XAS line shape is the same for all three samples (4% Eu-doped not shown here) and shows an overwhelming prevalence of Eu 2+ . , The results obtained by the XPS and XAS analyses thus demonstrate unequivocally that Eu atoms enter into the Bi 2 Te 3 lattice as Eu 2+ . In addition, previous transport results on Eu-doped Bi 2 Te 3 bulk crystals have shown an increase of p-type doping with rising europium content, which is also indicative of Eu atoms replacing Bi with less valence electrons.…”