深圳大学学报理工版

采用密度矩阵重整化群(density-matrix-renormalization-group, DMRG)方法,研究梯状光晶格中排斥相互作用费米气体的基态属性.研究表明,Zeeman场能够激发系统的相分离(完全极化相和部分极化相),而自旋轨道耦合效应能抑制相分离,使整个晶格处于部分极化相,在不同的强弱排斥相互作用系统中,极化率会随自旋轨道耦合改变表现出不同的变化规律.

The density-matrix-renormalization-group(DMRG)method is used to numerically calculate the ground state of repulsively interacting Fermi atoms loaded in optical ladder lattices. It is found that the system exhibits the spatial separation of a fully spin-polarized phase from the partially polarized phase for the suitable intensity of Zeeman field without the effect of spin-orbit coupled atoms. The spin-orbit coupling drives the fully spin-polarized phase to the partially spin-polarized phase in the whole system. The spin polarizations of weak and strong repulsively interacting systems vary differently with spin-orbit interaction strength.

引言
1 理论模型
2 结果及分析
3 结语

图1 双开链晶格模型<br/>Fig.1 Open ladder lattice model

图1 双开链晶格模型
Fig.1 Open ladder lattice model

图2 粒子数密度分布(t=1)<br/>Fig.2 The particle density under weakly and strongly repulsive interaction(t=1)

图2 粒子数密度分布(t=1)
Fig.2 The particle density under weakly and strongly repulsive interaction(t=1)

图3 粒子数密度分布(t=2)<br/>Fig.3 The particle density under weakly and strongly repulsive interaction(t=2)

图3 粒子数密度分布(t=2)
Fig.3 The particle density under weakly and strongly repulsive interaction(t=2)

图4 t=2,N=40,V=10,λ=0情况下系统的相图<br/>Fig.4 Phase diagram for t=2,N=40,V=10,λ=0

图4 t=2,N=40,V=10,λ=0情况下系统的相图
Fig.4 Phase diagram for t=2,N=40,V=10,λ=0

图5 不同排斥作用下系统基态能量(t=2, N=40, V=10, λ=0)<br/>Fig.5 Ground-state energy as a function of h with different repulsive interaction

图5 不同排斥作用下系统基态能量(t=2, N=40, V=10, λ=0)
Fig.5 Ground-state energy as a function of h with different repulsive interaction

图6 粒子数密度分布(t=2)<br/>Fig.6 The particle density with different spin-orbit coupling interaction(t=2)

图6 粒子数密度分布(t=2)
Fig.6 The particle density with different spin-orbit coupling interaction(t=2)

图7 不同排斥作用下极化率随λ的变化(t=2,N=40,V=10,h=0.15)<br/>Fig.7 The polarization as a function of λ with different repulsive interaction (t=2,N=40,V=10,h=0.15)

图7 不同排斥作用下极化率随λ的变化(t=2,N=40,V=10,h=0.15)
Fig.7 The polarization as a function of λ with different repulsive interaction (t=2,N=40,V=10,h=0.15)

图8 t=2,N=40,V=10,λ=1下不同排斥作用下系统基态能量<br/>Fig.8 Ground-state energy as a function of h with different repulsive interaction for t=2, N=40, V=10, λ=1

图8 t=2,N=40,V=10,λ=1下不同排斥作用下系统基态能量
Fig.8 Ground-state energy as a function of h with different repulsive interaction for t=2, N=40, V=10, λ=1

图9 链间耦合强度在t=2, U=60自旋向上和自旋向下的粒子数密度随λ的变化<br/>Fig.9 The spin up and down density as function of spin-orbit interaction under t=2 and U=60

图9 链间耦合强度在t=2, U=60自旋向上和自旋向下的粒子数密度随λ的变化
Fig.9 The spin up and down density as function of spin-orbit interaction under t=2 and U=60

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备注

引言

1 理论模型

2 结果及分析

3 结语

期刊信息

备注

引言

1 理论模型

2 结果及分析

3 结 语

期刊信息

3 结语