Multitip Near-Field Scanning Thermal Microscopy.

A theory is presented to describe the heat flux radiated in the near-field regime by a set of interacting nanoemitters held at different temperatures in vacuum or above a solid surface. We show that this thermal energy can be focused and even amplified in spots that are much smaller than those obtained with a single thermal source. We also demonstrate the possibility to locally pump heat using specific geometrical configurations. These many body effects pave the way to a multitip near-field scanning thermal microscopy that could find broad applications in the fields of nanoscale thermal management, heat-assisted data recording, nanoscale thermal imaging, heat capacity measurements, and infrared spectroscopy of nano-objects.