Fermion dynamical symmetry and strongly-correlated electrons: A comprehensive model of high-temperature superconductivity
Mike Guidry1(), Yang Sun2(), Lian-Ao Wu3(), Cheng-Li Wu4()
1. Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996, USA 2. School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China 3. IKERBASQUE, Basque Foundation for Science, 48011 Bilbao, Spain, and Department of Theoretical Physics and History of Science, Basque Country University (EHU/UPV), Post Office Box 644, 48080 Bilbao, Spain 4. Department of Physics, Chung-Yuan Christian University, Chungli, Taiwan 320, China
We review application of the SU(4) model of strongly-correlated electrons to cuprate and iron-based superconductors. A minimal self-consistent generalization of BCS theory to incorporate antiferromagnetism on an equal footing with pairing and strong Coulomb repulsion is found to account systematically for the major features of high-temperature superconductivity, with microscopic details of the parent compounds entering only parametrically. This provides a systematic procedure to separate essential from peripheral, suggesting that many features exhibited by the high-Tc data set are of interest in their own right but are not central to the superconducting mechanism. More generally, we propose that the surprisingly broad range of conventional and unconventional superconducting and superfluid behavior observed across many fields of physics results from the systematic appearance of similar algebraic structures for the emergent effective Hamiltonians, even though the microscopic Hamiltonians of the corresponding parent states may differ radically from each other.
Corresponding Author(s):
Mike Guidry,Yang Sun,Lian-Ao Wu,Cheng-Li Wu
引用本文:
. [J]. Frontiers of Physics, 2020, 15(4): 43301.
Mike Guidry, Yang Sun, Lian-Ao Wu, Cheng-Li Wu. Fermion dynamical symmetry and strongly-correlated electrons: A comprehensive model of high-temperature superconductivity. Front. Phys. , 2020, 15(4): 43301.
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The broken particle number symmetry can be restored by particle-number projection, but in practice this procedure may not be necessary as we are dealing with a system having a very large number of fermions.
