Thermoelectric power of MgB$_{2-x}$Be$_x$

J. S. Ahn; E. S. Choi; W. Kang; D. J. Singh; E. J. Choi

doi:10.1103/physrevb.65.214534

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Thermoelectric power of MgB$_{2-x}$Be$_x$

J. S. Ahn·E. S. Choi·W. Kang·D. J. Singh·E. J. Choi

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Abstract

We investigated thermoelectric power $S(T)$ of MgB$_{2-x}$Be$_{x}$ ($x=0$, 0.2, 0.3, 0.4, and 0.6). $S(T)$ decreases systematically with $x$, suggesting that the hole density increases. Our band calculation shows that the increase occurs in the $σ$-band. With the hole-doping, $T_{c}$ decreases. Implication of this phenomenon is discussed within the BCS framework. While the Mott formula explains only the linear part of $S(T)$ at low temperature, incorporation of electron-phonon interaction enables us to explain $S(T)$ over wide temperature range including the anomalous behavior at high temperature.

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J. S. Ahn, E. S. Choi, W. Kang, D. J. Singh, E. J. Choi. 2002-02-26. Thermoelectric power of MgB$_{2-x}$Be$_x$. https://doi.org/10.1103/physrevb.65.214534

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