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
Views 3361      Downloads 201
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
Article Tools
Follow on us
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.
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
G. Jeffrey Snyder and E. S. Toberer, "Complex thermo- electric materials" Nature Mater. , Vol.7, pp.105, 2008.
M.Cutler and N.F.Mott, "Observation of Anderson Localiz- ation in an Electron Gas", Phys. Rev. Vol. 181, pp.1336, 1969.
B. Kubala, J. Konig, and J. Pekola, "Violation of the Wiedemann-Franz Law in a Single-Electron Transistor ", Phys. Rev. Lett., Vol. 100, pp. 066801, 2008 .
J. Liu, Q. F Sun, and X. C. Xie, "Enhancement of the thermoelectric figure of merit in a quantum dot due to the Coulomb blockade effect ",Phys. Rev. B., Vol. 81, pp. 245323, 2010.
Y. Dubi and M. D.Ventra, "Colloquium: Heat flow and thermoelectricity in atomic and molecular junctions", Phys. Mod. Rev., Vol.83, pp.131, 2011.
M. Turek and K. A. Matveev, "Cotunneling thermopower of single electron transistors", Phys. Rev. B., Vol. 65, pp. 115332, 2002 .
J. Koch, F. von Oppen, Y. Oreg, and E. Sela, "Thermopower of single-molecule devices", Phys. Rev. B., Vol. 70, pp. 19510, 2004 .
B. Kubala and J. Konig, "Quantum-fluctuation effects on the thermopower of a single-electron transistor",Phys. Rev. B., Vol. 73, pp.195316 ,2006 .
X. Zianni, "Coulomb oscillations in the electron thermal conductance of a dot in the linear regime",Phys. Rev. B ., Vol. 75, pp.045344, 2007 .
D. Boese and R. Fazio, "Thermoelectric effects in Kondo -correlated quantum dots",Europhys. Lett. , Vol. 56, pp. 576, 2001 .
B. Dong and X. L. Lei, "Effect of the Kondo correlation on the thermopower in a quantum dot",J. Phys.: Condens. Matter ., Vol. 14, pp. 11747, 2002.
M. Krawiec and K. I. Wysokinski, "Thermoelectric effects in strongly interacting quantum dot coupled to ferromagnetic leads",Phys. Rev. B .,Vol. 73, pp.075307, 2006.
R. Sakano, T. Kita, and N. Kawakami, "Thermopower of Multiorbital Kondo Effect via Single Quantum Dot System at Finite Temperatures",J. Phys. Soc. Jpn. 76, pp. 074709, 2007.
R. Scheibner, H. Buchmann, D. Reuter, M. N. Kiselev, and L. W. Molenkamp, "Thermopower of a Kondo Spin- Correlated Quantum Dot",Phys. Rev. Lett.,Vol. 95, pp. 176602, 2005 .
M. Yoshida and L. N. Oliveira, "Thermoelectric effects in quantum dots ", Physica B., Vol. 404, pp.3312, 2009.
P.Trocha and J.Barnas, "Large enhancement of thermo- electric effects in a double quantum dot system due to interference and Coulomb correlation phenomena", Phys. Rev. B., Vol.85, pp. 085408, 2012.
C. M. Finch, V. M. Garcia-Suarez, and C. J. Lambert, "Giant thermopower and figure of merit in single-molecule devices",Phys. Rev. B ., Vol.79, pp.033405, 2009.
Y. S. Liu and X. F. Yang, "Enhancement of thermoelectric efficiency in a double-quantum-dot molecular junction",J. Appl. Phys., Vol.108, pp. 023710, 2010.
O. Karlstrom, H. Linke, G. Karlstrom, and A. Wacker,"Increasing thermoelectric performance using coherent transport",Phys. Rev. B., Vol.84, pp.113415, 2011.
D. Segal,"Thermoelectric effect in molecular junctions: A tool for revealing transport mechanisms", Phy. Rev. B., Vol.72, pp. 165426, 2005.
B. Ludoph and J. M. van Ruitenbeek, "Thermopower of atomic-size metallic contacts",Phys. Rev. B., Vol. 59, pp.12290, 1999.
P. Reddy, S. Y. Jang, R. A. Segalman, and A. Majumdar, "Thermoelectricity in Molecular Junctions",Science Vol.315, pp.1568, 2007,.
S. K. Yee, J. A. Malen, A. Majumdar, and R. A. Segalman, "Thermoelectricity in Fullerene-Metal Heterojunctions",Nano Lett., Vol.11, pp.4089, 2011.
J. P. Bergfield and C.A. Stafford,"Thermoelectric Signatures of Coherent Transport in Single-Molecule Heterojunctions", Nano Lett., Vol. 9, pp.3072, 2009.
R. Q. Wang, L. Sheng, R. Shen, B. Wang, and D. Y. Xing, "Thermoelectric Effect in Single-Molecule-Magnet Junctions", Phy. Rev. Lett ., Vol.105, pp.057202, 2010.
Z. Zhang, L. Jiang, R. Wang, B. Wang, and D. Y. Xing, "Thermoelectric-induced spin currents in single-molecule magnet tunnel junctions", Appl. Phy. Lett., Vol. 97, pp.242101, 2010.
P. S. Cornaglia, G. Usaj, and C. A. Balseiro, "Tunable charge and spin Seebeck effects in magnetic molecular junctions", Phy. Rev. B., Vol. 86, pp.041107(R), 2012.
C. Timm, F. Elste, "Spin amplification, reading, and writing in transport through anisotropic magnetic molecules", Phys. Rev. B., Vol. 73, pp.235304, 2006.
Y. Meir, N.S. Wingreen, "Landauer formula for the current through an interacting electron region", Phys. Rev. Lett., Vol. 68 , pp.2512, 1992.
H. Haug, A. Jauho, Quantum Kinetics in Transport and Optics of Semiconductors, Springer-Verlag, Berlin, 1996.
Peng-Bin Niu, Yu-Ying Zhang, Qiang Wang, Yi-Hang Nie, "Quantum transport through anisotropic molecular magnets: Hubbard Green function approach", Phys. Lett. A ., Vol.376 , pp.1481, 2012.
Qing-feng Sun, Hong Guo, "Double quantum dots: Kondo resonance induced by an interdot interaction", Phys. Rev. B., Vol. 66, pp.155308, 2002 .
M. Tolea, B.R. Bułka, "Theoretical study of electronic transport through a small quantum dot with a magnetic impurity", Phys. Rev. B., Vol. 75, pp.125301, 2007 .
Science Publishing Group
1 Rockefeller Plaza,
10th and 11th Floors,
New York, NY 10020
Tel: (001)347-983-5186