Abstracts Book - IMRC 2018

• SC6-O013 Invited Talk
THERMAL TRANSPORT AND ENERGY DISSIPATION IN
NANOSCALE CONDUCTORS
Fabian Menges 1 , Fabian Koenemann 2 , Nico Mosso 2 , Tino Wagner 3 , Andreas Stemmer 3 ,
Johannes Gooth 4 , Bernd Gotsmann 2
1 University of Colorado at Boulder, Physics, United States. 2 IBM Research Zurich, , Switzerland.
3 Eidgenössische Technische Hochschule Zürich, , Switzerland. 4 Max Planck Institute for
Chemical Physics of Solids, , Germany.
Heat and charge transport in nanoscale conductors are inherently coupled. This
has tremendous impact on the operation of scaled electronic devices and
motivates the combined characterization of both thermal and electronic
material properties down to the atomic scale. In this talk we will present
experimental approaches to study heat conduction and dissipation processes
based on scanning probe microscopy techniques and micro electromechanical
systems (MEMS) with integrated temperature sensors. We will first show how
the real-space imaging of Joule and Peltier effects down to the scale of a few
nanometers enables quantifying electrical and thermal contact resistances to
individual nanowires [1-3]. Next, we will highlight how spatially averaging
measurements with MEMS sensors permits the study of anomalous heat and
charge transport processes in scaled conductors. For this purpose, we will first
report on experiments that prove the validity of the Wiedemann-Franz law for
ordinary metals down to the atomic scale [2]. Subsequently, we will report on
recent studies that show a strong violation of the Wiedemann Franz law in a
nanobeam of the Weyl semimetal tungsten diphosphide (WP 2 )[3]. We will
discuss this observation in relation to a hydrodynamic transport regime at low
temperatures, and provide clear evidence that both thermal and electrical
transport in WP 2 are fundamentally limited by the quantum-mechanical
uncertainty principle applied to energy dissipation.
References:
[1] F. Menges et al., Temperature mapping of operating nanoscale devices by
scanning probe thermometry, Nature Communications 7(10874), 2016
[2] F. Menges et al., Local thermometry of self-heated nanoscale devices,
Electron Device Meeting (IEDM) IEEE International, 15-8, 2016.
[3] T. Wagner et al., Combined scanning probe electronic and thermal
characterization of an indium arsenide nanowire, Beilstein Journal of
Nanotechnology 9 (1), 129-136, 2018