1887
banner image
No data available.
Please log in to see this content.
You have no subscription access to this content.
No metrics data to plot.
The attempt to load metrics for this article has failed.
The attempt to plot a graph for these metrics has failed.
Enhancement in the figure of merit of p-type Bi100−xSbx alloys through multiple valence-band doping
Rent:
Rent this article for
USD
10.1063/1.4740262
/content/aip/journal/apl/101/5/10.1063/1.4740262
http://aip.metastore.ingenta.com/content/aip/journal/apl/101/5/10.1063/1.4740262
View: Figures

Figures

Image of FIG. 1.
FIG. 1.

Dependence of the energies of the various band extrema on composition x in Bi100−xSbx alloys at T = 0 K (compiled from Refs. 10–13). At the L-points of the Brillouin zone, the symmetric and antisymmetric bands are inverted between elemental Bi and Sb, leading to a Dirac point near x = 5 at. % fraction. The T-point valence band is the upper valence band of the semimetal Bi, but in elemental Sb, the holes are inside the Brillouin zone in three distorted ellipsoidal pockets near the H-points. This band becomes the upper valence band for x > 18. As in most solids, temperature can make band extrema shift by 100 meV between liquid nitrogen and room temperatures, an effect that is secondary in wide-gap semiconductors, but has a very important relative influence on the present diagram.

Image of FIG. 2.
FIG. 2.

Comparison of thermoelectric properties of single crystal Bi81.05Sb18.2Sn0.75 sample between in the trigonal plane and along the trigonal axis directions. (a) Thermal conductivity κ, (b) thermopower S, (c) electrical resistivity ρ, and (d) figure of merit zT as functions of temperature. Points are experimental data and lines are added to guide the eye.

Image of FIG. 3.
FIG. 3.

Thermoelectric properties of single crystal Bi100−xSbxSn0.75 samples for x = 11.6, 18.2, 19.5, 22.9, 26.5, 30, and 37 from 2 K to 400 K. All properties were measured with the heat flux and current in the trigonal plane. (a) Thermal conductivity κ, (b) electrical resistivity ρ, and (c) thermopower S as functions of temperature. The insert shows the figure of merit zT as a function of temperature. Points are experimental data and lines are added to guide the eye.

Image of FIG. 4.
FIG. 4.

(a) Pisarenko’s plot of thermopower versus hole concentration at T = 80 K for all measured samples in this study. Solid line and dashed line are calculated for the valence bands at the H-points and the valence band at the T-point, respectively. Points are experimental data. Carrier density of each sample was obtained from Hall measurement assuming a Hall prefactor of unity. (b)-(d) Schematic band diagrams for the three different Sb concentration regimes shown. Relative position of each band and the position of Fermi energies (EF ) are not to scale.

Loading

Article metrics loading...

/content/aip/journal/apl/101/5/10.1063/1.4740262
2012-08-01
2014-04-23
Loading

Full text loading...

This is a required field
Please enter a valid email address
752b84549af89a08dbdd7fdb8b9568b5 journal.articlezxybnytfddd
Scitation: Enhancement in the figure of merit of p-type Bi100−xSbx alloys through multiple valence-band doping
http://aip.metastore.ingenta.com/content/aip/journal/apl/101/5/10.1063/1.4740262
10.1063/1.4740262
SEARCH_EXPAND_ITEM