We are delighted to share our recent work on "First-principles study of large gyrotropy in MnBi for infrared thermal photonics", published in Physical Review B. It talks about how nonreciprocal gyrotropic materials have attracted significant interest recently in material physics, nanophotonics, and topological physics. Most of the well-known nonreciprocal materials, however, only show nonreciprocity under a strong external magnetic field and within a small segment of the electromagnetic spectrum.
Here, through first-principles density-functional theory calculations, we show that due to strong spin-orbit coupling manganese-bismuth (MnBi) exhibits nonreciprocity without any external magnetic field and a large gyrotropy in a broadband long-wavelength infrared regime. Further, we design a multilayer structure based on MnBi to obtain a maximum degree of spin-polarized thermal emission at 7 µm.
The connection established here between large gyrotropy and the spin-polarized thermal emission points to the potential use of MnBi to develop spin-controlled thermal photonics platforms.
To know more about the paper click here.