Dates: August 16 - 20, 2021

Location: PCS Video Conference (further details: pcs@ibs.re.kr)

Scientific coordinators: Alexei Andreanov (IBS PCS)

                                     Sergej Flach (IBS PCS)

                                     Bohm-Jung Yang (SNU / IBS CCES)

Organizers: Gileun Lee (IBS PCS)

                    Jaehee Kwon (IBS PCS)

Overview:

Systems with macroscopic degeneracies are natural testbeds for novel and interesting phases of matter when subject to perturbations. The degeneracies are typically fragile and any perturbation no matter how small is relevant. Flatbands - dispersionless bands in single particle systems - are one example of such macroscopic degeneracy. When analysing the degeneracies there are two major difficulties: how does one find the degeneracies - they are typically the result of finetuning and are hard to come by - and what happens when a perturbation is added - which usually has a non-perturbative effect making standard weak coupling methods unapplicable. Therefore devising new methods to obtain/find degeneracies and developing tools to understand the effect of various perturbations is of prime importance. The aim of this conference is to bring together experts in the field to get an overview of the current state and most recent results and advances in the field.

Topics include:

1. • Finetuning and perturbations of flatbands
   

2. • Effects of symmetries
   

3. • Many-body interactions
   

4. • Applications