Efficient photothermal therapy with spatially localized high-temperature generation by refractory absorber

Abstract

In this work, we propose a titanium nitride (TiN)-based ultra-broadband perfect absorber from the ultraviolet to near-infrared wavelength ranges with the average absorptivity up to 96.7%. The weighted absorption efficiency of the solar radiation energy reaches 95.6%. In addition, photothermal therapy is conducted on such absorber, showing the effectively confined local high-temperature in the vicinity of the device. The steady-state temperature reaches 327 K at a depth of 3 mm beneath the tissue surface, leading to the efficient optical damage exceeding 90% for the surrounding diseased tissue only by a 3-min illumination. Such moderate photothermal therapy adequately meets the requirements for inactivating tumor cells and hold wide applications in the photo-biomedical science and technology.