  The recent isolation of atomically thin black phosphorus by mechanical
exfoliation of bulk layered crystals has triggered an unprecedented interest,
even higher than that raised by the first works on graphene and other
two-dimensional, in the nanoscience and nanotechnology community. In this
Perspective we critically analyze the reasons behind the surge of experimental
and theoretical works on this novel two-dimensional material. We believe that
the fact that black phosphorus band gap value spans over a wide range of the
electromagnetic spectrum that was not covered by any other two-dimensional
material isolated to date (with remarkable industrial interest such as thermal
imaging, thermoelectrics, fiber optics communication, photovoltaics, etc), its
high carrier mobility, its ambipolar field-effect and its rather unusual
in-plane anisotropy drew the attention of the scientific community towards this
two-dimensional material. Here we also review the current advances, the future
directions and the challenges in this young research field.
