Calculation of Thermoelectric Transport Properties in Heterostructures

Abstract

We present a model that can predict the Seebeck coefficient of different interfaces. Within this model we solve the Poisson equation and Schrödinger equation self-consistently to obtain the potential profile across the interface. Then we use the nonequilibrium Green's function (NEGF) method to calculate the transport properties across the interface. We apply our model to a ZnO grain boundary, describing the boundary as a back-to-back Schottky barrier. The potential profile in the considered system is similar to a rigid-shift potential, and thus the Seebeck coefficient obtained from the rigid-shift potential shows no deviation in comparison with the Seebeck coefficient obtained from the self-consistent potential.

Ineffectiveness of energy filtering at grain boundaries for thermoelectric materials

“…We use the nonequilibrium Green's function (NEGF) method [24][25][26][27] to calculate ballistic transport through a double Schottky barrier. The Green's function of the system is given by…”

Synergy between defects, charge neutrality and energy filtering in hyper-doped nanocrystalline materials for high thermoelectric efficiency

“…It is a well-known effect and has been widely studied in many experiments and by using theoretical models. [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] Nonetheless, it has been shown so far to be not adequate for a breakthrough in the field of thermoelectrics. Our work indicates an additional mechanism and a synergy between defects, charge neutrality and energy filtering that can take place in hyper-doped nanocrystalline materials upon thermal annealing at high T a and can lead to this end.…”

Intramolecular thermoelectric-like effects in field-effect molecular nanoelectronic devices

“…Discussion and conclusion. -The introduction and calculation of the intramolecular thermoelectric-like coefficient (IMTLC) is unprecedented, and is mentioned for the Many recent theoretical studies based on the Green's function (GF) method have paid attention to the electrical conductance and thermopower of mesoscopic, nanoscale and molecular systems [2,[34][35][36]. However, the GF has not so far been applied in the analysis of the intramolecular conductive and thermoelectric behavior, because of its limitations which are due to the incorporation of statistical thermodynamic approaches based on the molecular density of states and its variations without any partitioning of the molecular space (e.g., into atomic or sectional parts).…”