Quantization of conductivity of nanotechnological point contact. Simple   derivation of the Landauer formula
  A simple methodical derivation for Landauer quantization of the conductivity is derived as a simple consequence of the Bohr quantization laws. The level of explanation corresponds to high-school level of Physics education and can be used as popular lecture for students. The purpose of the work is to introduce students in an achievement of nano-technology which is relevant to the future electronics. Using only the fundamental laws of quantization students can understand a contemporary experimental research and to follow future development in the field. 
T.M. Mishonov and M.V. Stoev