標題: | Seebeck coefficient of thermoelectric molecular junctions: First-principles calculations |
作者: | Liu, Yu-Shen Chen, Yu-Chang 電子物理學系 Department of Electrophysics |
關鍵字: | ab initio calculations;Fermi level;molecular electronics;Seebeck effect |
公開日期: | 1-五月-2009 |
摘要: | A first-principles approach is presented for the thermoelectricity in molecular junctions formed by a single molecule contact. The study investigates the Seebeck coefficient considering the source-drain electrodes with distinct temperatures and chemical potentials in a three-terminal geometry junction. We compare the Seebeck coefficient in the amino-substituted and unsubstituted butanethiol junctions and observe interesting thermoelectric properties in the amino-substituted junction. Due to the novel states around the Fermi levels introduced by the amino substitution, the Seebeck coefficient could be easily modulated by using gate voltages and biases. When the temperature in one of the electrodes is fixed, the Seebeck coefficient varies significantly with the temperature in the other electrode and such dependence could be modulated by varying the gate voltages. As the biases increase, richer features in the Seebeck coefficient are observed, which are closely related to the transmission functions in the vicinity of the left and right Fermi levels. |
URI: | http://dx.doi.org/10.1103/PhysRevB.79.193101 http://hdl.handle.net/11536/7259 |
ISSN: | 1098-0121 |
DOI: | 10.1103/PhysRevB.79.193101 |
期刊: | PHYSICAL REVIEW B |
Volume: | 79 |
Issue: | 19 |
起始頁: | 0 |
結束頁: | 0 |
顯示於類別: | 期刊論文 |