9:00 AM - 9:15 AM
▲ [7a-A405-1] Nanoscale Temperature Mapping of Current-heated Narrow Metal Wires
Keywords:nanothermometry, near-field, local Joule heating
Thermometry techniques with high spatial resolution on sub-micron scales have attracted great interest in recent years, being motivated by applications in a variety of areas such as microelectronic devices, dissipative quantum systems, and even living cells. However, realization of nanoscale temperature mapping is not an easy task: Development of high performance nanothermometric technique with negligible influence on the measured temperature is highly demanded. Here, we report a novel radiative-type thermometer which can overcome the diffraction-limit and achieve nanoscale spatial resolution. It is a home-made thermal near-field optical microscope, which is so sensitive to detect thermally induced fluctuating electromagnetic evanescent waves. The detected thermal near-field signal is then directly related to the electromagnetic energy density of thermal near-field radiation, which is temperature dependent. We will discuss the local temperature detection with the near-field approach, and demonstrate the real-space temperature mapping of a current-heated narrow metal wire. A hot-spot is directly imaged on the metal wire by our experimental technique, which should be due to the current-crowding induced strong energy dissipation.