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arXiv · 0906.3528

Haldane charge conjecture in one-dimensional multicomponent fermionic cold atoms

H. Nonne·P. Lecheminant·S. Capponi·G. Roux·E. Boulat
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Abstract

A Haldane conjecture is revealed for spin-singlet charge modes in 2N-component fermionic cold atoms loaded into a one-dimensional optical lattice. By means of a low-energy approach and DMRG calculations, we show the emergence of gapless and gapped phases depending on the parity of $N$ for attractive interactions at half-filling. The analogue of the Haldane phase of the spin-1 Heisenberg chain is stabilized for N=2 with non-local string charge correlation, and pseudo-spin 1/2 edge states. At the heart of this even-odd behavior is the existence of a spin-singlet pseudo-spin $N/2$ operator which governs the low-energy properties of the model for attractive interactions and gives rise to the Haldane physics.

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H. Nonne, P. Lecheminant, S. Capponi, G. Roux, E. Boulat. 2010-01-25. Haldane charge conjecture in one-dimensional multicomponent fermionic cold atoms. https://doi.org/10.1103/physrevb.81.020408

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