Diffusion thermopower in graphene

作者：Vaidya R G^*; Kamatagi M D; Sankeshwar N S; Mulimani B G

来源：Semiconductor Science and Technology, 2010, 25(9): 092001.

DOI：10.1088/0268-1242/25/9/092001

The diffusion thermopower of graphene, S-d, is studied for 30 < T < 300 K, considering the electrons to be scattered by impurities, vacancies, surface roughness and acoustic and optical phonons via deformation potential couplings. S-d is found to increase almost linearly with temperature, determined mainly by vacancy and impurity scatterings. A departure from linear behaviour due to optical phonons is noticed. As a function of carrier concentration, a change in the sign of vertical bar S-d vertical bar is observed. Our analysis of recent thermopower data obtains a good fit. The limitations of Mott formula are discussed. Detailed analysis of data will enable a better understanding of the scattering mechanisms operative in graphene.

• 出版日期2010-9