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arXiv · 1106.1262

Seebeck effect in dilute two-dimensional electron systems: temperature dependencies of diffusion and phonon-drag thermoelectric powers

S. Y. Liu·X. L. Lei·Norman J. M. Horing
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Abstract

Considering screeening of electron scattering interactions in terms of the finite-temperature STLS theory and solving the linearized Boltzmann equation (with no appeal to a relaxation time approximation), we present a theoretical analysis of the low-temperature Seebeck effect in two-dimensional semiconductors with dilute electron densities. We find that the temperature ($T$) dependencies of the diffusion and phonon-drag thermoelectric powers ($S_d$ and $S_g$) can no longer be described by the conventional simple power-laws. As temperature increases, $|S_d|/T$ decreases when $T\gtrsim 0.1 ε_F$ ($ε_F$ is the Fermi energy), while $|S_g|$ first increases and then falls, resulting a peak located at a temperature between Bloch-Grüneisen temperature and $ε_F$.

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S. Y. Liu, X. L. Lei, Norman J. M. Horing. 2011-06-07. Seebeck effect in dilute two-dimensional electron systems: temperature dependencies of diffusion and phonon-drag thermoelectric powers. https://arxiv.org/abs/1106.1262

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