Broadband single-channel coherent perfect absorption with a perfect magnetic mirror.

Two-channel coherent perfect absorption (CPA) enables absorption modulation as well as perfect absorption in a very simple way. However, because of its narrow and discrete operable wavelength range, the CPA has been limited to specific applications. In this work, we theoretically and experimentally demonstrate broadband single-channel CPA operable from the visible to near-infrared wavelengths, using an ultrathin absorbing material on a pseudo perfect magnetic mirror. Our simple yet effective method can be applied to various applications such as solar cells, thermophotovoltaics, and stealth technology.