Journal of Nanomedicine & Nanotechnology

Peltier cooling in carbon nanotube circuits

5^th International Conference on Nanotek & Expo

November 16-18, 2015 San Antonio, USA

Serhii Shafraniuk

Northwestern University, USA

Posters-Accepted Abstracts: J Nanomed Nanotechnol

Abstract:

Conversion of the heat energy directly into electricity and vice versa attracts a significant attention nowadays. Systematic study of thermoelectric phenomena allows for better understanding of the intrinsic mechanisms of the energy transformation and dissipation on the nanoscale. A bias electric voltage DV, applied to a conducting sample, pulls the charge carriers, thereby inducing a finite electric current Ie= GeDV, where Ge is the electric conductance. Since the bias voltage, DV also induces an inhomogeneity of charge carrier density along the sample, it leads to a finite temperature difference hot and cold DT=Thot -Tcold, where Thot(cold) is the temperature of the hot (cold) part of the sample. The thermoelectric effect is described as DV=SDT where S is a linearresponse, two-terminal property known as Seebeck coefficient. Thermoelectric effect is measured using two sequentially-connected carbon nanotube (CNT) field-effect transistors (FETs), each with charge carriers of opposite sign, either electrons or holes, whose concentration is controlled by the side gate electrodes. A change DT of the intrinsic temperature is determined from the change of the position and width of spectral singularities manifested in the experimental curves of the source-drain electric conductance. We deduce an impressive Peltier effect ±DT=57 K inside the CNT associated with cooling and heating, depending on the direction of the electric current. The effect can be utilized for building thermoelectric devices having a figure of merit up to cold ZT=7.5>>1 and the cooling power density Pcooling~80 kW/cm2.

Biography :

Email: s-shafraniuk@.edu