Mott insulator-density ordered superfluid transition and‘shamrock transition’in a frustrated triangle lattice  

作　　者：Ce Wang Yu Chen 

机构地区：[1]School of Physics Science and Engineering,Tongji University,Shanghai,200092,China [2]Institute for Advanced Study,Tsinghua University,Beijing,100084,China [3]Graduate School of China Academy of Engineering Physics,Beijing,100193,China

出　　处：《Communications in Theoretical Physics》2024年第3期157-164,共8页理论物理通讯（英文版）

基　　金：supported by the Beijing Natural Science Foundation(Z180013)(YC);National Natural Science Foundation of China(NSFC)under Grant No.12174358(YC)and No.11734010(YC and CW);MOST Grant No.2016YFA0301600(CW)。

摘　　要：Density order is usually a consequence of the competition between long-range and short-range interactions.Here we report a density ordered superfluid emergent from a homogeneous Mott insulator due to the competition between frustrations and local interactions.This transition is found in a Bose–Hubbard model on a frustrated triangle lattice with an extra pairing term.Furthermore,we find a quantum phase transition between two different density ordered superfluids,which is beyond the Landau–Ginzburg(LG)paradigm.A U(1)symmetry is emergent at the critical point,while the symmetry in each density ordered superfluid is Z_(2)×Z_(3).We call the transition a‘shamrock transition’,due to its degenerate ground state in the parameter space being a shamrock-like curve rather than a circle in an LG-type transition.Effective low energy theories are established for the two transitions mentioned above and we find their resemblance and differences with clock models.

关 键 词：frustrated magnets SUPERFLUID mott insulator density wave ordered phase clock model 

分 类 号：O469[理学—凝聚态物理]