Remote Joule heating by a carbon nanotube

Abstract

Minimizing Joule heating remains an important goal in the design of electronic devices. The prevailing model of Joule heating relies on a simple semiclassical picture in which electrons collide with the atoms of a conductor, generating heat locally and only in regions of non-zero current density, and this model has been supported by most experiments. Recently, however, it has been predicted that electric currents in graphene and carbon nanotubes can couple to the vibrational modes of a neighbouring material, heating it remotely. Here, we use in situ electron thermal microscopy to detect the remote Joule heating of a silicon nitride substrate by a single multiwalled carbon nanotube. At least 84% of the electrical power supplied to the nanotube is dissipated directly into the substrate, rather than in the nanotube itself. Although it has different physical origins, this phenomenon is reminiscent of induction heating or microwave dielectric heating. Such an ability to dissipate waste energy remotely could lead to improved thermal management in electronic devices.

Role of Remote Interfacial Phonon (RIP) Scattering in Heat Transport Across Graphene/SiO2 Interfaces

“…7 Later, Baloch et al estimated from their measurements on multi-walled CNTs (~25 nm in diameter) that the contribution by RIP scattering is g RIP  0.02 W m -1 K -1 when driven by high source-drain biases. 11 (We discuss below our estimates related to Baloch's work, and note that in reaching their conclusion, they used a low thermal contact conductance by vibration modes of 0.004 W m -1 K -1 , which they independently measured. 15 )…”

“…4 ) In addition, our findings are also in contrast to the apparently dominant contribution of RIP scattering to the interfacial heat conduction of CNTs on SiO 2 substrates, predicted by calculations of Rotkin et al 7 for single-wall CNTs and the experiments of Baloch et al for multi-wall CNTs. 11 Rotkin et al calculated that, for single-walled CNTs on SiO 2 , the thermal conductance per unit length due to RIP scattering is g RIP  0.1 W m -1 K -1 when the doping level is 0.1 e/nm (i.e., ~2.5  10 12 cm -2 ) and the lateral field is >2 V m -1 . Baloch et al…”

“…7,11 RIP scattering could be an order of magnitude stronger when the charge carriers are driven under high electric field, 7 due to e.g., excitation of high-energy SPP modes in the polar substrates by hot electrons in graphene or CNTs. Thus, the low-energy of charge carriers in our unbiased graphene could contribute to low G RIP compared to those measured in biased CNTs.…”

Vanadium dioxide nanowire-based microthermometer for quantitative evaluation of electron beam heating

“…To date, robust solutions for quantitative measurement of local temperature and heat flow at nanoscale dimensions are very limited [1][2][3][4][5][6][7][8] . In particular, inhomogeneous temperature distributions at these size scales are not easily probed with typical small-scale thermal measurements such as infrared thermometers or scanning thermal microscopy 2,8 .…”

“…Experimentally, scanning thermal microscopy 2 requires a complicated setup, which is difficult to combine with TEM. The melting point of a material can be used to quantify temperature, but this is typically only a single-point or singletemperature detection [4][5][6][7] , especially when trying to measure the temperature of individual small particles. As environmental interactions become more accessible through modern in situ TEM instrumentation, it is essential to distinguish temperature effects from other electron beam effects 11,12 .…”