Adiabatic continuity and broken symmetry in many-electron systems: A variational perspective

作者：Baeriswyl D^*

来源：Annalen der Physik, 2011, 523(8-9): 724-731.

DOI：10.1002/andp.201100044

• Strongly correlated electrons
• variational wave functions
• adiabatic continuity

Variational wave functions are very useful for describing the panoply of ground states found in interacting many-electron systems. Some particular trial states are "adiabatically" linked to a reference state, from which they borrow the essential properties. A prominent example is the Gutzwiller ansatz, where one starts with the filled Fermi sea. A simple soluble example, the anisotropic XY chain, illustrates the adiabatic continuity of this class of wave functions. To describe symmetry breaking, one has to modify the reference state accordingly. Alternatively, a quantum phase transition can be described by a pair of variational wave functions, starting at weak and strong coupling, respectively.

• 出版日期2011-8