Thermoelectric Efficiency of Nanowires with Long Range Surface Disorder

Abstract

AbstractThermoelectric efficiency of nanowires is shown to be enhanced when they have disordered surfaces with long range correlations. To show this effect, one needs to solve Schrödinger equation in a surface disordered waveguide geometry as a model for nanowires and employ the resulting transmission to analyze nanowires as feasible heat engines. Using the linear response theory in determining the efficiency of the possible heat engine device based on silicon nanowires is although useful to point out the overall behavior with respect to the continuous incident electron energy, it says nothing about its performance as a heat engine. A nonlinear response theory is proved to be necessary to find out the specific energies at which the nanowire has greater efficiency at max power as a thermoelectric device. The efficiency at the maximum power shows that some nanowires with specific surface disorder structure is more appropriate to use as a heat engine than the others. The possibility of engineering the transmission of electrons in the nanowires to increase their efficiency maybe an answer to the demand of highly efficient thermoelectric semiconductor materials in future.KeywordsTransmission SpectrumHeat EngineSilicon NanowiresLinear Response TheoryIncident Electron EnergyThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.