Exploring Nanoscale Thermal Transport with Microcalorimetric Tools

Nanoscale heat transport plays an important role in energy conversion and thermal management. Therefore, understanding how nanoscale heat transport can be tuned is critical for developing novel technologies, including cooling strategies for microelectronics and nanostructured materials and devices for high-efficiency energy conversion. To probe nanoscale thermal transport phenomena, many calorimetric tools and approaches have been developed. Specifically, suspended microcalorimeters featuring picowatt resolution have been extensively employed for measuring thermal transport in low-dimensional materials, radiative heat transfer in nanoscale gaps, and between subwavelength structures. Further, scanning calorimetric probes, combined with atomic force microscopy and scanning tunneling microscopy, have been utilized for probing atomic-scale thermal transport and near-field thermal radiation. Here, we discuss these advances in calorimetric tools and their use for studying nanoscale thermal transport. We conclude by discussing open experimental challenges and highlighting the importance of future developments in subpicowatt resolution calorimetric tools for accessing unexplored nanoscale thermal transport phenomena.