Chiral symmetry restoration in (2+1)-dimensional $QED$ with a   Maxwell-Chern-Simons term at finite temperature
  We study the role played by a Chern-Simons contribution to the action in the $QED_3$ formulation of a two-dimensional Heisenberg model of quantum spin systems with a strictly fixed site occupation at finite temperature. We show how this contribution affects the screening of the potential which acts between spinons and contributes to the restoration of chiral symmetry in the spinon sector. The constant which characterizes the Chern-Simons term can be related to the critical temperature $T_c$ above which the dynamical mass goes to zero. 
Raoul Dillenschneider and Jean Richert