Electrical Properties of Lead Telluride

Abstract

Samples of n-type PbTe crystals with different electron concentrations (n=2×1017∼5×1019/cc) were prepared by impurity doping or by heating in the vapor of lead. The electrical properties of these crystals were independent of the kind of impurities and depended only on the electron concentration. The electron mobilities of our samples were proportional to n−⅓ at 77°K, and to n−4/3 at 4.2°K. As the conduction electrons in our samples are degenerate at these temperatures, the experimental results mentioned above suggests that the conduction electrons in PbTe crystals are scattered mainly by acoustical mode at 77°K and by neutral imperfections at 4.2°K. Since the electron mobility in PbTe becomes very large at 4.2°K (e.g., 1∼4×106 cm2/v-sec), this material is quite suitable for the experimental studies of the quantum transport phenomena. To investigate such phenomena, the Hall and magnetoresistive effects of n-type PbTe crystals were measured at 4.2°K in a pulsed magnetic field up to 170 kgauss. In the specimens with relatively low electron concentrations (e.g., n≃3×1017/cc), the magnetoresistive effect had a single minimum at about 77 kgauss in a transverse magnetic field, and at about 55 kgauss in a longitudinal field. This minimum should correspond to the situation where the Landau level with l = 1 coincides with the Fermi level in the PbTe crystals.

Thermoelectric Properties of the Compounds AgPbmLaTem+2

“…The mobility tends to decrease as the carrier concentration increases. This is in agreement with carrier-concentration dependent mobility at a finite temperature for n-type PbTe samples; for example, μ ≈ n −1/3 at 77 K and μ ≈ n −4/3 at 4.2 K . The mobilities of the La analogs are lower than PbTe with a carrier concentration of 5 × 10 18 cm −3 (∼1500 cm 2 /(V s) at 300 K), are comparable to the AgPb 18 SbTe 20 (∼800 cm 2 /(V s) at 300 K), and are much higher than the AgPb 18 BiTe 20 (∼200 cm 2 /(V s) at 300 K) .…”

Exploring Resonance Levels and Nanostructuring in the PbTe−CdTe System and Enhancement of the Thermoelectric Figure of Merit

“…The mobility tends to decrease as the CdTe concentration increases because CdTe precipitates in the PbTe matrix play a role as electron scatterers. For comparison the mobility of PbTe with a carrier concentration of 5 × 10 18 cm -3 is ∼1500 cm 2 /(V s) at 300 K. 25 The carrier-concentration-dependent mobility at a finite temperature for n-type PbTe samples is µ ≈ n -1/3 at 77 K and µ ≈ n -4/3 at 4.2 K. 26 The temperature-dependent mobility of PbTe-x% CdTe -0.055% PbI 2 (x ) 1, 3, 7) follows a quadratic power law of µ ≈ T -λ (λ ) 2.1), which is in good agreement with those of n-type PbTe samples. 27 The temperature dependences of the total and lattice thermal conductivity of samples are plotted in Figure 3(c).…”

“…For comparison the mobility of PbTe with a carrier concentration of 5 × 10 18 cm −3 is ∼1500 cm 2 /(V s) at 300 K . The carrier-concentration-dependent mobility at a finite temperature for n-type PbTe samples is μ ≈ n −1/3 at 77 K and μ ≈ n −4/3 at 4.2 K . The temperature-dependent mobility of PbTe− x % CdTe−0.055% PbI 2 ( x = 1, 3, 7) follows a quadratic power law of μ ≈ T −λ (λ = 2.1), which is in good agreement with those of n-type PbTe samples …”

Components of strong magnetoresistance in Mn implanted Ge

“…Similar linear behavior has also been observed in other high mobility semiconductors, such as InSb 23,24 and PbTe. 25,26 A renewed interest in strong linear magnetoresistance has been triggered by observation of the phenomenon in doped silver chalcogenides, 27,28 followed by similar observations in InSb 29 and InAs. 30 Current interpretation of the effect is associated with strong disorder, where current paths deviate from the applied voltage due to spatial fluctuations of Hall mobility.…”