Direct electronic measurement of Peltier cooling and heating in graphene.

I. J. Vera-Marun,B. J. van Wees,J. J. van den Berg,F. K. Dejene

doi:10.1038/ncomms11525

I. J. Vera-Marun, B. J. van Wees + Show 2 more

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https://doi.org/10.1038/ncomms11525

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Journal: Nature Communications	Publication Date: May 10, 2016
Citations: 45	License type: CC BY 4.0

Affiliation: University of Groningen

Abstract

Thermoelectric effects allow the generation of electrical power from waste heat and the electrical control of cooling and heating. Remarkably, these effects are also highly sensitive to the asymmetry in the density of states around the Fermi energy and can therefore be exploited as probes of distortions in the electronic structure at the nanoscale. Here we consider two-dimensional graphene as an excellent nanoscale carbon material for exploring the interaction between electronic and thermal transport phenomena, by presenting a direct and quantitative measurement of the Peltier component to electronic cooling and heating in graphene. Thanks to an architecture including nanoscale thermometers, we detected Peltier component modulation of up to 15 mK for currents of 20 μA at room temperature and observed a full reversal between Peltier cooling and heating for electron and hole regimes. This fundamental thermodynamic property is a complementary tool for the study of nanoscale thermoelectric transport in two-dimensional materials.

Highlights

Thermoelectric effects allow the generation of electrical power from waste heat and the electrical control of cooling and heating
The Seebeck effect is the generation of a voltage due to a temperature difference and is quantified by the Seebeck coefficient or thermopower of a material, S 1⁄4 À DV/DT, used for temperature sensing in thermocouples
The results are consistent with the reversibility and electron-hole symmetry expected for the linear response of the Peltier effect

Summary

Introduction

Thermoelectric effects allow the generation of electrical power from waste heat and the electrical control of cooling and heating. Thanks to an architecture including nanoscale thermometers, we detected Peltier component modulation of up to 15 mK for currents of 20 mA at room temperature and observed a full reversal between Peltier cooling and heating for electron and hole regimes This fundamental thermodynamic property is a complementary tool for the study of nanoscale thermoelectric transport in two-dimensional materials. The Peltier effect is a reversible thermodynamic phenomenon that depends linearly on the current, so it is fundamentally different from the irreversible Joule heating[17] As both thermoelectric coefficients are related by the second Thomson relation[18] P 1⁄4 ST, where T is the reference temperature, it follows that in graphene the Peltier coefficient P (and its associated cooling or heating action) can be controlled in both magnitude and sign. We successfully describe the observed temperature profile in the device using a simple one-dimensional model

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