Galvanomagnetic phenomena in platinum antimonide in high magnetic fields

Abstract

Magnetoresistance and Hall effect measurements in the narrow band gap semiconductor platinum antimonide, were made in pulsed magnetic fields from 10 to 200 kG at temperatures 2, 4.2, 77, and 300 °K. Quantum oscillations of magnetoresistance were observed at 2 and 4.2 °K. The experimental results compared with theory show that the valence band of PtSb2 is not spherical. As the Hall coefficient of PtSb2 is magnetic field‐independent it is possible to use PtSb2 samples in measurements of high magnetic fields at different temperatures.

Investigation of the correlation between stoichiometry and thermoelectric properties in a PtSb2single crystal

“…Large changes in the Seebeck coefficient are also observed in FeSb 2 , when the carrier concentration is varied. 7, 8 The thermal conductivity has a peak at low temperature characteristic for metallic samples and it is significantly lower than the values reported by Abdullaev et al (39 W K -1 m -1 at 300 K), 20 which can be explained by the deviating stoichiometry of our sample. The value of the thermal conductivity measured here is 20 W K -1 m -1 at room temperature.…”

“…The electron mobility is lower than the electron-hole mobility and for low charge carrier concentrations (10 16 -10 17 cm -3 ) an electron mobility of ~3000 cm 2 V -1 s -1 at 77 K is reported, 15 while the hole mobility can reach c. 6000 cm 2 V -1 s -1 at 77 K. 11 At room temperature the electron mobility is reported to be from one to a few hundred cm 2 V -1 s -1 . 15, [18][19][20] The calculated band structure is shown in Fig. 9.…”

Thermoelectric performance in electron and hole doped PtSb$_2$

“…Recently, such bands have been reported in the cubic pyrite material PtSb 2 , which has a high S = 250 µVK −1 [2]. Bulk PtSb 2 can be both metallic and semiconducting for deviations from the ideal stoichiometry and it can be n-and p-type doped with charge carrier concentrations spanning several orders of magnitude (10 16 cm −3 to 10 20 cm −3 ), as observed for different synthesis methods and parameters [3][4][5][6][7][8]. While p-type PtSb 2 (by Ir doping on the Pt site) gives a high metallic conductivity and large Seebeck coefficient [2], n-type PtSb 2 (by Sb deficiency) gives a large Seebeck coefficient and thermal conductivity between 0 and 300 K [9].…”

Thermoelectric performance of electron and hole doped PtSb2

“…3 Bulk PtSb 2 can be both metallic and semiconducting for deviations from the ideal stoichiometry, and it can be n-and p-type doped with charge carrier concentrations spanning several orders of magnitude (10 16 cm À3 to 10 20 cm À3 ), as observed for different synthesis methods and parameters. [4][5][6][7][8][9] While p-doping (by Ir doping on the Pt site) gives a high metallic conductivity and large Seebeck coefficient, 3 n-doping (by Sb deficiency) gives a large Seebeck coefficient and thermal conductivity between 0 and 300 K. 10 PtSb 2 has a high mobility due to a small difference in the electronegativities of Pt and Sb (2.28 and 2.05, respectively). 11 In the present work, we address the effect of electron and hole doping in PtSb 2 , which has a melting temperature of 1500 K, 12 on r and S from 300 K to 800 K. We study the powerfactor and the figure of merit for both types of doping.…”