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Smectic Spin-Orbital Intertwined Order in a Hexagonal Lattice

Yongqiang Li, Jian‐Min Yuan, Xiaoji Zhou, Xiaopeng Li

Published Jan 13, 2021• 0 citations
OpenAlex

Abstract

Frustrated lattices provide a versatile ground for fascinating quantum many-body physics. Here, we study an ultracold atomic system of two-component (pseudospin-$1/2$) Bose gases in the $p$-orbital band of a hexagonal lattice, which exhibits frustration in an orbital setting. The potential spontaneous symmetry-breaking orders in this complex system are classified by symmetry analysis. We find the interplay of orbital frustration and strong interaction leads to unconventional Mott and superfluid phases with smectic spin-orbital intertwined orders, in spite of the complete absence of spin-orbital interaction in the Hamiltonian. The spontaneously formed orbital polarization forms circulating textures in the lattice, with opposite circulation in the two-pseudospin components. Our study implies many-body correlations in a multi-orbital setting could induce rich spin-orbital intertwined physics without requirement of engineering spin-orbit interaction.

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