Luminescence of hexagonal boron nitride (hBN) has puzzled researchers for long time. In standard solid state physics textbooks direct band gap semiconductors are considered efficient light emitters while indirect ones are regarded as inefficient. Hexagonal boron nitride seems to defy this rule. In fact hBN emits light in the ultraviolet with an efficient comparable to… Read More
My code to calculate non-linear response in solids and nanostructure is finally online. The first tutorials are available, and soon I will finish the other ones. Full free to use it and let me know if you find bugs or strange things.
In this work we compare the optical absorption of extended systems calculated starting from the density-density and current-current linear response formalisms within the equilibrium many-body perturbation theory(MBPT). We show how, using the latter, one can incur in errors due to quasiparticle lifetimes, electron-hole interaction or the presence of a Drude tail. These errors are found… Read More