Luttinger liquid

Summary

A Luttinger liquid, or Tomonaga–Luttinger liquid, is the generic low-energy state of interacting gapless particles in one dimension. Its excitations are not quasiparticles, as in a Fermi liquid, but collective density waves described by a free boson field. Its correlation functions decay as power laws whose exponents depend on one interaction parameter $K$. The name was introduced by Duncan Haldane in 1981, after the models of Sin-Itiro Tomonaga (1950) and Joaquin Luttinger (1963).