Field theory of the random flux model |
| |
| Institution: | 1. Theoretische Physik III, Ruhr-Universität Bochum, 44780 Bochum, Germany;2. Cavendish Laboratory, Madingley Road, Cambridge CB3 OHE, UK;1. Saudi Center for Theoretical Physics, Dhahran, Saudi Arabia;2. Theoretical Physics Group, Faculty of Sciences, Chouaib Doukkali University, PO Box 20, 24000 El Jadida, Morocco;3. Sino-French Institute of Nuclear Engineering and Technology, Sun Yat-sen University, Guangzhou 510275, China;1. H. Amirkhanov Institute of Physics of the Daghestan Federal Research Centre of the Russian Academy of Sciences, Makhachkala 367010, Russia;2. Daghestan Federal Research Centre of the Russian Academy of Sciences, Makhachkala 367000, Russia;1. Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China;2. Collaborative Innovation Center of IFSA (CICIFSA), Shanghai Jiao Tong University, Shanghai 200240, China;3. Center for Gravitation and Cosmology, College of Physical Science and Technology, Yangzhou University, Yangzhou 225009, China;4. School of Aeronautics and Astronautics, Shanghai Jiao Tong University, Shanghai 200240, China;1. Hamilton Mathematics Institute and School of Mathematics, Trinity College, Dublin 2, Ireland;2. Institute Lorentz for Theoretical Physics, Leiden University, P.O. Box 9506, Leiden 2300RA, The Netherlands |
| |
| Abstract: | The random flux model (defined here as a model of lattice fermions hopping under the influence of maximally random link disorder) is analysed field theoretically. It is shown that the long range physics of the model is described by the supersymmetric version of a field theory that has been derived earlier in connection with lattice fermions subject to weak random hopping. More precisely, the field theory relevant for the behaviour of n-point correlation functions is of non-linear σ model type, where the group GL(n|n) is the global invariant manifold. It is argued that the model universally describes the long range physics of random phase fermions and provides further evidence in favour of the existence of delocalised states in the middle of the band in two dimensions. The same formalism is applied to the study of non-Abelian generalisations of the random flux model, i.e. N-component fermions whose hopping is mediated by random U(N) matrices. We discuss some physical applications of these models and argue that, for sufficiently large N, the existence of long range correlations in the band centre (equivalent to metallic behaviour in the Abelian case) can be safely deduced from the RG analysis of the model. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
