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A detailed study of charge transport properties of synthetic and genomic DNA sequences is reported. Genomic sequences of the Chromosome 22, λ-bacteriophage, and D1s80 genes of Human and Pygmy chimpanzee are considered in this work, and compared with both periodic and quasiperiodic (Fibonacci) sequences of nucleotides. Charge transfer efficiency is compared for all these different sequences, and large variations in charge transfer efficiency, stemming from sequence-dependent effects, are reported. In addition, basic characteristics of tunneling currents, including contact effects, are described. Finally, the thermoelectric power of nucleobases connected in between metallic contacts at different temperatures is presented.

We present a theoretical analysis of thermoelectric transport in the nonlinear regime. The thermopower and thermoconductance at finite temperature gradient are calculated numerically for a double barrier structure using Landauer Büttiker like formula. The thermopower is found to oscillate with the chemical potential. Thermopower can either be negative or positive which is well correlated with the behavior of the electric conductance. The thermal conductance is positive definite showing that the heat energy is always transferred from hot end to cold end. As the chemical potential is varied, nonlinear thermal conductance exists plateau-like features.

In the present work, the in-plane electron thermopower of semiconducting size-quantized films with nonparabolic energy band in a classically strong magnetic field, which is parallel to the film normal, are investigated. It was shown that, for the degenerate electron gas thermopower is a function of film thickness and electron density: for arbitrary thickness thermopower is oscillating function, with the period as a function of concentration, but with respect to concentration thermopower is monotonically increasing function. It is shown that in the case of ultrathin films (quantum wells) thermopower increases, as thickness decreases. This result is in agreement with the experimental dates on GaAs quantum wells.

Thermoelectric and thermomagnetic properties of graphene are analyzed using Boltzmann transport equation within the relaxation time approximation. Influence of temperature, charge carrier density and magnetic field on the thermopower and figure of merit is taken into account in the presence of different scattering processes. It is observed the magnetic field results in the increase of thermopower and figure of merit in the acoustical phonon scattering process, while they are reduced by charged impurity scattering.

The doping dependence of the thermopower of cuprate superconductors in the normal-state is studied within the $t$–$j$ model. It is shown that with a proper modification of the bare electron dispersion in the $t$–$j$ model, the experimental results of the doping dependence of the normal-state thermopower are qualitatively reproduced. In particular, the theory shows that a pseudogap-generated split of the van Hove peak in the density of states appears in the underdoped and optimally doped regimes, however, this split is absent from the overdoped regime. Concomitantly, the strong asymmetry of the spectral conductivity near the electron Fermi surface emerges, where the peak in the spectral conductivity appears always below the electron Fermi surface in the underdoped and optimally doped regimes, while it appears above the electron Fermi surface in the overdoped regime. This strong asymmetry of the spectral conductivity leads to the unusual behaviors of the normal-state thermopower from the underdoped regime to the overdoped regime.