# We introduce a new method for thermal conductivity measurements in nanosheets and nanowires

Our new study showing how bolometric effect can be used to measure the thermal conductivity of nanosheets and nanowires is just accepted to IOP 2D Materials. The method relies on local heating of a nanosheet suspended over a circular hole with a focused laser beam. This results in a bolometric response on the material, i.e. the local resistivity over the suspended part changes, leading to a measurable signal when measured appropriately. Then, through modelling, the resistivity change can be calculated with thermal conductivity being a fitting parameter. The method provides a superior sensitivity as the resistivity changes as small as a part per million can be measured using a lock-in technique. This also reduces the need for the local heating making the method suitable for studying the thermal conductivity in the vicinity of the temperature induced thermal conductivity changes. Of course, like every other thermal conductivity measurement technique, there are limitations to this method as well. First of all, if there is no bolometric response from the material, such as the residual resistivity of metals at low temperature, the method doesn’t work. Also, a complicated analysis is required to study the semiconducting materials. Overall, we believe this method is a milestone in measuring the thermal conductivity of nanosheets and nanowires.

Serkan

Dr. Kasırga got his Ph.D. from the University of Washington on experimental solid state physics. He attended lectures of world-renowned physicists such as Nobel laureate Prof. David Thouless, Prof. Arkady Levanyuk and Boris Spivak on solid state physics.