Prediction of a gapless topological Haldane liquid phase in a one-dimensional cold polar molecular lattice

Abstract

We show that ultracold two-component fermionic dipolar gases in an optical lattice with strong two-body on-site loss can be used to realize a tunable effective spin-one model. Fermion number conservation provides an unusual constraint that i (S z i ) 2 is conserved, leading to a unique topological liquid phase in one dimension, which can be thought of as the gapless analog of the Haldane gapped phase of a spin-one Heisenberg chain. The properties of this phase are calculated numerically via the infinite time-evolving block decimation method and analytically via a mapping to a one-mode Lüttinger liquid with hidden spin information.

d-wave superfluidity in optical lattices of ultracold polar molecules

“…The amplitudes and signs of J ⊥ , J z , V , and W can be tuned independently [30] by tuning the external dc electric field and applying external microwave fields [17][18][19][21][22][23][24][25]29,[42][43][44][45][46]. The tunneling amplitude t (assumed to be positive throughout the paper) can be tuned by adjusting the depth of the optical lattice.…”

“…This system can be used to implement lattice Hamiltonians based on rotational states of polar molecules [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32]. Specifically, two rotational states of the molecules can be used as an effective spin-1/2 degree of freedom, while dipole-dipole interactions mediate "spin"-dependent coupling between molecules.…”

Controllable quantum spin glasses with magnetic impurities embedded in quantum solids

“…Powerful microwave dressing techniques borrowed from the polar-molecule literature [54][55][56][57][58][59][60][61][62][63][64][65][66][67][68][69][70][71][72][73] can be used to access a great variety of Hamiltonians beyond the one given in Eq. (6) …”

Long-range and frustrated spin-spin interactions in crystals of cold polar molecules

“…Compared to ions, polar molecules can easily be trapped in standard optical lattice potentials of different geometries or -by aligning their dipole moments -be stabilized in a high density crystalline phase [31][32][33][34]. The combination of these exceptional properties make polar molecules one of the most promising systems for large scale simulation of non-trivial quantum spin models [35][36][37][38][39][40][41][42].…”