Atomistic study of electronic structure of PbSe nanowires

Lead Selenide (PbSe) is an attractive 'IV-VI' semiconductor material to design optical sensors, lasers, and thermoelectric devices. Improved fabrication of PbSe nanowires (NWs) enables the utilization of low dimensional quantum effects. The effect of cross-section size (W) and channel orientation on the band structure of PbSe NWs is studied using an 18 band sp(3)d(5) tight-binding theory. The band gap increases almost with the inverse of the W for all the orientations indicating weak symmetry dependence. [111] and [110] NWs show higher ballistic conductance for the conduction and valence band compared to [100] NWs due to the significant splitting of the projected L-valleys in [100] NWs. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3592577]