EXPERIMENTAL EXPLORATION OF NEAR-FIELD RADIATIVE HEAT TRANSFER

This paper presents an in-depth review of ongoing experimental research efforts to fundamentally understand the strong near-field enhancement of radiative heat transfer and make use of the underlying physics for various novel applications. Compared to theoretical studies on near-field radiative heat transfer (NFRHT), its experimental demonstration has not been explored as much until recently due to technical challenges in precision gap control and heat transfer measurement. However, recent advances in micro-/nanofabrication and nanoscale instrumentation/control techniques as well as unprecedented growth in materials science and engineering have created remarkable opportunities to overcome the existing challenges in the measurement and engineering of NFRHT. Beginning with the pioneering works in 1960s, this paper tracks the past and current experimental efforts of NFRHT in three different configurations (i.e., sphere-plane, plane-plane, and tip-plane). In addition, future remarks on how to address current challenges in the experimental research of NFRHT are briefly discussed.