Unconventional Condensates in Solid State Physics

Studying different symmetry breaking ground states of matter is perhaps the most fundamental object of modern low temperature solid state physics. These exotic ground states include superconductivity and density waves of different kinds. The physics of conventional s-wave superconductivity and the quasi-one dimensional conventional charge and spin density waves are now well known due to intense research over the past fifty years. However, since the discovery of heavy fermion superconductors in 1979, organic superconductors in 1980 and high temperature superconductors in 1986 it turned out that interestingly most of these superconductors are unconventional: their order parameters are momentum dependent. Since then exploration of the microscopic origin of this unconventional pairing mechanism has been and still is in the forefront of research. This book is dedicated to the theoretical study of unconventional ordering in the particle-hole sector, that is in density waves. Quasi-one dimensional charge and spin density wave ground states are investigated. We explore the electronic Raman response, study the instability due to phonon exchange and also impurity physics in great detail.