Thermopower of Benzenedithiol and C60 Molecular Junctions with Ni and Au Electrodes

详细信息    查看全文

• 作者：See Kei Lee ; Tatsuhiko Ohto ; Ryo Yamada ; Hirokazu Tada
• 刊名：Nano Letters
• 出版年：2014
• 出版时间：September 10, 2014
• 年：2014
• 卷：14
• 期：9
• 页码：5276-5280
• 全文大小：322K
• ISSN：1530-6992

文摘

We have performed thermoelectric measurements of benzenedithiol (BDT) and C₆₀ molecules with Ni and Au electrodes using a home-built scanning tunneling microscope. The thermopower of C₆₀ was negative for both Ni and Au electrodes, indicating the transport of carriers through the lowest unoccupied molecular orbital in both cases, as was expected from the work functions. On the other hand, the Ni鈥揃DT鈥揘i junctions exhibited a negative thermopower, whereas the Au鈥揃DT鈥揂u junctions exhibited a positive thermopower. First-principle calculations revealed that the negative thermopower of Ni鈥揃DT鈥揘i junctions is due to the spin-split hybridized states generated by the highest occupied molecular orbital of BDT coupled with s- and d-states of the Ni electrode.

Keywords:

Thermoelectricity; molecular junctions; thermopower; spin-splitting; density functional calculation