Thomas–Fermi screening is a theoretical approach to calculating the effects of electric field screening by electrons in a lattice.
For example, this model is a mainstay to describe coulomb screening in astrophysical situations. However, when the TF model is used to predict screening in metals where polaritons exist, it underestimates the intensity of screening produced by polaritons. Usually, The Thomas-Fermi wavevector reflects the chemical potential (fermi level, the electron concentration and, the elementary charge. For electrons, the chemical potential gets progressively worse for screening because the electrons satisfy the Pauli Exclusion Principle: Lower-energy electron states are already full, so the new electrons must occupy higher- and higher-energy states. To get more electrons into a given volume, progressively more energy is required to pack these additional electrons into that volume. If polaritons as used for coulomb screening, because the polariton is a boson, the Pauli Exclusion Principle and the chemical potential gradient that it generates are not applicable. As an extra bonus, The high density of polaritons could be supported by the formation of a Boss-Einstein condensate of polaritons cooper pairs formed when two oppositely polarized polaritons join at high polariton density with spins of +1 and -1 See Exciton-polariton mediated superconductivity http://www.google.com/url?sa=t&rct=j&q=&esrc=s&frm=1&source=web&cd=2&cad=rja&ved=0CEEQFjAB&url=http%3A%2F%2Farxiv.org%2Fpdf%2F0907.2374&ei=OiZ0UYHzMu6q4AOPpYGoAg&usg=AFQjCNFtjU1E7NA8OUkAPGyIVjexpNDNnw&sig2=Haz8wTpb-uxeLs20FTXQWQ If such polariton superconductivity is possible, resistance free electrical transmission at refractory temperatures below 2600C might be possible in a properly configure nano-system. Cheers: Axil
