Two conduction bands with very different effective masses are usually at the X point in half-Heusler Brillouin zone. Our orbital phase diagram provides feasible strategies to converge these two for thermoelectric enhancement.

The structure and the electronic properties of single-walled zigzag BN and B3C2N3 nanotubes (n, 0; n=4–10) were investigated using first-principles calculations based on a density functional theory. A plane–wave basis set with periodic boundary conditions in conjunction with Vanderbilt ultrasoft pseudo-potential was employed. The energy gap of ZB3C<su...

Valence-band and conduction-band edges of ultrathin oxides SiO2, HfO2, Hf0.7Si0.3O2, and Al2O3 grown on silicon and their shifts upon sequential metallization with ruthenium have been measured using synchrotronradiation-excited x-ray, ultraviolet, and inverse photoemissions. From these techniques, the offsets between the valence-band and conduction-band edges of the oxides, and the ruthenium me...

PbSe is a surprisingly good thermoelectric material due, in part, to its low thermal conductivity that had been overestimated in earlier measurements. The thermoelectric figure of merit, zT, can exceed 1 at high temperatures in both p-type and n-type PbSe, similar to that found in PbTe. While the p-type lead chalcogenides (PbSe and PbTe) benefit from the high valley degeneracy (12 or more at hi...

By combining temperature-dependent resistivity and Hall effect measurements, we investigate donor state energy in Si-doped \b{eta}-Ga2O3 films grown using metal-organic vapor phase epitaxy (MOVPE). High magnetic field measurements (H = +/-90 kOe) showed non-linear resistance for T < 150 K revealing two-band conduction. Further analyses revealed carrier freeze-out characteristics both bands yiel...