@article{narendra_norouzzadeh_vashaee_kim_2017, title={Doping induced enhanced density of states in bismuth telluride}, volume={111}, ISSN={0003-6951 1077-3118}, url={http://dx.doi.org/10.1063/1.4989602}, DOI={10.1063/1.4989602}, abstractNote={Power factor enhancement through resonant doping is explored in Bi2Te3 based on a detailed first-principles study. Of the dopant atoms investigated, it is found that the formation of resonant states may be achieved with In, Po, and Na, leading potentially to a significant increase in the thermoelectric efficiency at room temperature. While doping with Po forms twin resonant state peaks in the valence and conduction bands, the incorporation of Na or In results in the resonant states close to the valence band edge. Further analysis reveals the origin of these resonant states. Transport calculations are also carried out to estimate the anticipated level of enhancement.}, number={23}, journal={Applied Physics Letters}, publisher={AIP Publishing}, author={Narendra, Namita and Norouzzadeh, Payam and Vashaee, Daryoosh and Kim, Ki Wook}, year={2017}, month={Dec}, pages={232101} }
 @article{narendra_kim_2017, title={Toward enhanced thermoelectric effects in Bi2Te3/Sb2Te3heterostructures}, volume={32}, ISSN={0268-1242 1361-6641}, url={http://dx.doi.org/10.1088/1361-6641/aa539d}, DOI={10.1088/1361-6641/aa539d}, abstractNote={The possibility of enhanced thermoelectric properties through nanostructuring is investigated theoretically in a p-type Bi2Te3/Sb2Te3 heterostructure. A multi-scale modeling approach is adopted to account for the atomistic characteristics of the interface as well as the carrier/phonon transport properties in the larger scales. The calculations clearly illustrate the desired impact of carrier energy filtering at the potential barrier by locally boosting the power factor over a sizable distance in the well region. Further, the phonon transport analysis illustrates a considerable reduction in the thermal conductivity at the heterointerface. Both effects are expected to provide an effective means to engineer higher zT in this material system.}, number={3}, journal={Semiconductor Science and Technology}, publisher={IOP Publishing}, author={Narendra, Namita and Kim, Ki Wook}, year={2017}, month={Jan}, pages={035005} }