Chiral spin liquid in moat lattices or how a moat protects against ordering?
| Date/Time: | Thursday, 22 Oct 2015 - Saturday, 24 Oct 2015 |
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| Location: | PHYSICS Hall 3 |
| Phone: | 515-294-5630 |
| Channel: | College of Liberal Arts and Sciences |
| Actions: | Download iCal/vCal | Email Reminder |
Frustrated lattices are remarkable for their capacity to host rich physics. Examples include lattices having moat-like band structures, i.e., a band with infinitely degenerate energy minima attained along a closed line in the Brillouin zone. It is entirely the effect of correlations which lifts this degeneracy and leads to an amazing variety of completely new quantum many-body states. If such an optical lattice is populated with bosons, the degeneracy prevents their condensation. At half-filling and hard-core repulsion, the system is equivalent to the s=1/2 XY model at a zero magnetic field, while the absence of condensation translates into the absence of magnetic order in the XY plane. In this talk I will argue that the frustration in such lattices stabilizes a variety of novel quantum spin liquid phases including a composite fermion state and a chiral spin liquid. These are topologically nontrivial ground states, having a bulk gap and chiral gapless edge excitations. The applications of the developed analytical theory include an explanation of recent numerical findings and a suggestion for the chiral spin liquid realizations in experiments with cold atoms.