Bilayer Quantum Hall Systems: Spin-Pseudospin Symmetry Breaking and Quantum Phase Transitions

摘要

We discuss and review recent advances in our understaning of quantum Hallsystems where additional quantum numbers associated with spin and/or layer(pseudospin) indices play crucial roles in creating exotic quantum phases.Among the novel quantum phases we discuss are the recently discovered cantedantiferromagnetic phase, the spontaneous interlayer coherent phase, and variousspin Bose glass phases. We describe the theoretical models used in studyingthese novel phases and the various experimental techniques being used to searchfor these phases. Both zero temperature quantum phase transitions and finitetemperature phase transitions are discussed. Emphasis in this article is on therecent developments in novel quantum phases and quantum phase transitions inbilayer quantum Hall systems where nontrivial magnetic ground states associatedwith spontaneous spin symmetry breaking play central role.