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arXiv · 1811.10944

Momentum distribution and tunneling density of states of one-dimensional Fermonic SU(N) Hubbard model

Shuang Liang·Deping Zhang·Wei Chen
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Abstract

We study the one-dimensional Fermionic Hubbard model with SU(N) spin symmetry in the incommensurate filling case. The basic properties of Green's function, momentum distribution and tunneling density of states of the system at low temperature are studied in the frame work of Luttinger liquid theory combined with Bethe Ansatz solutions for arbitrary interaction. In the strong interacting case, the system enters the spin-incoherent regime at intermediate temperature Espin < T < Ec and we obtain the Green's function and tunneling density of states by generalizing the path integral approach for the SU(2) case to the SU(N) case in this regime. The theoretical results we obtained agree qualitatively with the experiments on the one-dimensional alkaline earth atomic system with SU(N) spin symmetry. The similarities and difference between the one-dimensional SU(N) Fermionic Hubbard system at large N and the one-dimensional spinless Bosonic system are also investigated.

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Shuang Liang, Deping Zhang, Wei Chen. 2018-11-27. Momentum distribution and tunneling density of states of one-dimensional Fermonic SU(N) Hubbard model. https://doi.org/10.1088/1361-648x%2Fab04be

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