论文标题
具有吸引力的一维自旋1/2费米气体的激发光谱
Excitation Spectra of one-dimensional spin-1/2 Fermi gas with an attraction
论文作者
论文摘要
使用精确的Bethe Ansatz解决方案，我们严格研究具有吸引人相互作用的Spin-1/2 Fermi气体（称为Yang-Gaudin模型）的激发光谱。该模型的基本激发涉及粒子孔激发，孔激发和在对的Fermi海洋和未配对的费米子中添加颗粒。自旋扇形中的镁弹性刺激显示出与单个费米子的费米海的铁磁耦合。通过数值和分析求解该模型的Bethe Ansatz方程和热力学Bethe Ansatz方程，我们在Fulde-Ferrell-Larkin-Larkin-ovchinnikov（FFLO）类似于类似的状态的阶段获得了各种极化的激发能。对于较小的动量（长波长极限），在强烈的相互作用方向上，我们通过曲率校正，有效的质量以及对颗粒 - 孔孔的激发和未配对的费米子的粒子孔激发中的速度进行分析获得线性分散体。这种类型的粒子孔激发表现出了在配对和未配对的费米子内骨气模式集体运动的新分离。最后，我们还讨论了旋转扇形中的木否激发，以及bragg光谱法在测试这种分离的装置兴奋模式和单个费米子中的应用。
Using exact Bethe ansatz solution, we rigorously study excitation spectra of the spin-1/2 Fermi gas (called Yang-Gaudin model) with an attractive interaction. Elementary excitations of this model involve particle-hole excitations, hole excitations and adding particles in the Fermi seas of pairs and unpaired fermions. The gapped magnon excitations in spin sector show a ferromagnetic coupling to the Fermi sea of the single fermions. By numerically and analytically solving the Bethe ansatz equations and the thermodynamic Bethe ansatz equations of this model, we obtain excitation energies for various polarizations in the phase of the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO)-like state. For a small momentum (long-wavelength limit) and in the strong interaction regime, we analytically obtained their linear dispersions with curvature corrections, effective masses as well as velocities in particle-hole excitations of pairs and unpaired fermions. Such a type of particle-hole excitations display a novel separation of collective motions of bosonic modes within paired and unpaired fermions. Finally, we also discuss magnon excitations in spin sector and the application of the Bragg spectroscopy for testing such separated charge excitation modes of pairs and single fermions.
