Band structure and optical properties of black phosphorus

First, the authors calculate the frequency-dependent dielectric function of black phosphorus by using the band structure and wavefunctions obtained by the self-consistent pseudopotential calculation. Then by using these results, they discuss the optical properties of black phosphorus such as KPS, UPS, plasmon frequency and reflectance in visible, VUV and soft X-ray regions. Experimental results for all these optical properties are explained consistently using the theoretical results.