Schwinger Bosons Approaches to Quantum Antiferromagnetism
  These lectures review the large N Schwinger Bosons Mean Field approach to the quantum Heisenberg model. The method applies to ordered and disordered phases in all dimensions, at zero and at finite temperature. Extension to frustrated models is explained. An example for an experimentally useful application, is the temperature dependent staggered magnetization of the layered antiferromagnet. 
Assa Auerbach, Daniel P. Arovas