Once a body reaches a temperature greater than absolute zero, electromagnetic wave emissions are inevitable because of the increase in temperature. Radiative heat transfer has been broken down into two primary categories up to this point. These categories are based on the sample’s geometric dimension and the characteristic wavelength established by Wien’s displacement equation. The term ”far-field radiative heat transfer” refers to a kind of radiative heat transfer that occurs when the predominant wavelength is much shorter than the distance that separates the emitter and the receiver (FFRHT). In contrast, ”near-field radiative heat transfer” refers to the process of radiative heat transfer that occurs when the distance between the objects is comparable to or less significant than the wavelength of the radiation (NFRHT). The Stefan–Boltzmann rule dictates that the NFRHT between two substances
separated by a nanoscale vacuum gap must be greater than the black-body limit. The preponderance of evanescent waves or photon tunneling is to blame for this observation. The enhancement of the NFRHT was facilitated by the surface waves, which included surface phonon polaritons (SPhPs) and surface plasmon polaritons (SPPs), respectively. The introduction of coupling materials has the potential to trigger these waves. Because they can sustain SPhPs even at room temperature, dielectrics are ideal. This article discusses the current developments that have been made regarding materials that enable SPhPs and SPPs surface modes and boost radiative heat transfer. In this study, we developed a unique experimental setup to strictly control the XYZ and tilt motions of the sample while also maintaining the nano-gap spacing and parallelism of the arrangement. After that, we investigated the radiative heat flow between two parallel, MgF$_2$-dielectric-coated SiO$_2$ plates. With our measurements’ help, we could determine a distance of 700-nm. The experimental result for heat flow is comparable to the theoretical one, and enhanced heat flux is observed compared to the bulk SiO$_2$ silicon plates.
평행 플레이트 사이의 진공 간극이 나노 크기에 가까워지면 근거리 복사 열 전달이 블랙바디 한계를 초과합니다. 여기서는 샘플의 XYZ 및 기울기 움직임을 엄격하게 제어하고 나노캡 간격과 병렬성을 유지하는 새로운 실험 설정을 설계했습니다. 이후, 우리는 2개의 병렬 200 NM MGF$_2$ 유전 코팅된 SiO$_2$ 플레이트 사이의 복사 열 플럭스에 대한 실험을 수행했습니다. 우리의 측정을 통해 700NM까지 거리를 얻을 수 있습니다. 실험 열량 결과는 이론적인 결과와 비슷합니다. 게다가 열량 증분은 대량 SiO$_2$ 실리콘 플레이트에 비해 관찰됩니다.
