Enhancement of Thermoelectric Effects in a Single Molecular Magnet due to Resonance Tunnelling
American Journal of Modern Physics
Volume 3, Issue 2, March 2014, Pages: 37-44
Received: Jan. 19, 2014; Published: Feb. 20, 2014
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Authors
Jian-Hua Wang, Institute of Theoretical Physics, Shanxi University, Taiyuan, China
Wei-Ping Xu, Institute of Theoretical Physics, Shanxi University, Taiyuan, China
Yu-Ying Zhang, Department of Physics, Shanxi University, Taiyuan, China
Yi-Hang Nie, Institute of Theoretical Physics, Shanxi University, Taiyuan, China
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Abstract
Thermoelectric properties of the single molecular magnet coupled to two metal electrodes are investigated theoretically. For the infinite Coulomb interaction the singly-occupied states determine the effective transport channels. At the low temperature the thermopower and the figure of merit present the large values near bonding state level, and for the given temperature the thermopower and the figure of merit are significantly enhanced with coupling intensity decreasing. When Coulomb interaction is finite, the spectra of thermoelectric quantities split into two sets. The peaks of the thermopower and figure of merit corresponding to doubly-occupied transport channels are much larger than unity for the small coupling intensity. These results are useful for understanding and designing highly efficient thermoelectric devices based on molecular magnet.
Keywords
Molecular Magnet, Thermoelectric Effect, Coulomb Blockade
To cite this article
Jian-Hua Wang, Wei-Ping Xu, Yu-Ying Zhang, Yi-Hang Nie, Enhancement of Thermoelectric Effects in a Single Molecular Magnet due to Resonance Tunnelling, American Journal of Modern Physics. Vol. 3, No. 2, 2014, pp. 37-44. doi: 10.11648/j.ajmp.20140302.12
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