Figure 4. The dependence of T c (in K) on composition for Pb 1-x Sn x Te 1-y S y solid solution. The dotted line shows the stability limits for a solid solution according our data.
Figure 3. The dependence of T c (in K) upon composition for Pb 1-x Sn x Te 1-y Se y solid solution. The dotted lines show the stability limits for a solid solution.
... Typical R(T) plots for PbS x Se y Te 1-x-y and Pb 1-x Sn x Te 1-y Se y solid solutions. Curves 1-5 correspond to the samples of PbS x Se y Te 1-x-y with constant x=0.08 and y=0.21, 0.27, 0.34, 0.40, and 0.46, respectively. Curves 6-12 correspond to the samples of Pb 1-x Sn x Te 1-y Se y with constant x=0.2 and y=0, 0.05, 0.25, 0.33, 0.5, 0.67, and 0.83, respectively. The curves are shifted arbitrary along vertical axis. ...
Figure 8. Dependence of T c upon the concentration N i of different impurities for PbTe 0.92 S 0.08 . 1, Cd; 2, Ga; 3, In; 4, Tl; 5, Sb; 6, Bi; 7, Mn /20/. Dashed line corresponds to the isoelectronic impurity Se.
Figure 7. Temperature dependence of resistivity for PbTe 0.92 S 0.08 crystals doped with different amounts of In (on the left) and Se (on the right). The concentration of indium (in at.%): 1, 0.15; 2, 0.31; 3, 0.49; 4, 0.71. The concentration of Se in the samples of Pb(Te 1-y Se y ) 0.92 S 0.08 (in mol.%): 5, 21; 6, 27; 7, 34; 8, 40; 9, 46 /20/.
Figure 6. Temperature dependence of resistivity for Pb 1-x Sn x Te 1-y Se y crystals with fixed Sn concentration (x=0.2) and variable y /15/. 1, y=0; 2, y=0.05; 3, y=0.25; 4, y=0.33; 5, y=0.5; 6, y=0.67; 7, y=0.83. The insert shows the dependence of T c on y.
Figure 5. a - Local environment of off-center atom in ternary and quaternary solid solutions. Full and dotted circles show different positions of off-center atom. Figure b and c show the potential wells of off-center atom for ternary (solid line) and quaternary (dashed line) solid solutions for the case of high and low barrier height, respectively.
Figure 2. Dependence of T c on z for three quaternary solid solutions (Pb 1-x Ge x Te) 1-z (Pb 1-y Ge y Se) z : 1, x=0.025, y=0.04; 2, x=y=0.06; 3, x=y=0.08.
Figure 1. Temperature dependence of resistivity for (Pb 0.975 Ge 0.025 Te) 1-z (Pb 0.96 Ge 0.04 Se) z samples. 1, z=0; 2, z=0.42; 3, z=0.57; 4, z=0.67; 5, z=0.77; 6, z=0.86; 7, z=0.94; 8, z=1 /12/. The curves were arbitrary shifted along vertical axis. The arrows show the direction of temperature change during recording the curves.
Fig. 5. R(T) curves for Pb 1-x Sn x Te 0.95 S 0.05 samples. 1 - x=0.023, 2 - x=0.046, 3 - x=0.118, 4 - x=0.248, 5 - x=0.358, 6 - x=0.629. Curves 2, 3, 4, 5 are shifted up by 10, 20, 25 and 20 units, respectively. Samples 1-3 are of n-type, 4-6 - of p-type. Arrows indicate the direction of temperature change during recording the curves. The insert shows the dependence of T c on tin concentration.
Fig. 4. R(T) curves for Pb 0.8 Sn 0.2 Te 0.5 Se 0.5 sample, illustrating "quenching" effect. Curves were obtained during slow heating after quenching from 77 to 4.2 K (1) and during subsequent slow cooling (2) and slow heating (3).
Fig. 2. R(T) curves for Pb 1-x Sn x Te 0.75 Se 0.25 samples. 1 - x=0.075, 2 - x=0.2, 3 - x=0.3, 4 - x=0.5, 5 - x=0.625, 6 - x=0.85. Curves 2,3,6 are shifted up by 30, 50, and 80 units, respectively, and curve 4 is shifted down by 30 units. Samples 1,2 are of n-type, 3-6 - of p-type. Arrows indicate the direction of temperature change during recording the curves.
Fig. 1. Temperature dependence of resistivity R(T) for Pb 0.8 Sn 0.2 Te 1-y Se y samples. 1 - y=0, 2 - y=0.05, 3 - y=0.25, 4 - y=0.33, 5 - y=0.5, 6 - y=0.67, 7 - y=0.83. Curves 3-7 are shifted up by 35, 55, 75, 130, and 165 units, respectively. All samples are of n-type. Arrows indicate the direction of temperature change during recording the curves. The insert shows the dependence of T c on y.