标题： 自旋轨道耦合费米气体中的稳定半涡旋带隙孤子 显示英文标题

标题： Stable semivortex gap solitons in a spin-orbit-coupled Fermi gas

摘要： 我们展示了在二维费米自旋系统中，在Rashba型自旋轨道耦合与Zeeman分裂(ZS)组合作用下，存在具有旋量$0$和$1$的半涡旋(SV)孤子。在“重原子”近似下，该近似之前已用于玻色系统，通常的动能被忽略，从而产生具有带隙的线性谱。该模型包括由费米超流体密度泛函理论产生的有效Pauli自排斥，其幂次为$7/3$。在一般情况下，也包含了组间接触排斥。我们构建了一族占据谱带隙的SV型间隙孤子。通过系统模拟，在交叉排斥强度和化学势的参数平面上确定了SV孤子的稳定区域。稳定区域与反-Vakhitov-Kolokolov准则的预测一致，该准则是具有自排斥非线性的系统的一个相关必要稳定条件。我们还测试了SV孤子在ZS强度突然变化下的稳定性，这会导致由于系统组分之间的粒子转移而在孤子的自旋态中引发鲁棒振荡。 显示英文摘要

摘要： We demonstrate the existence of semivortex (SV) solitons, with vorticities $0$ and $1$ in the two components, in a two-dimensional (2D) fermionic spinor system under the action of the Rashba-type spin-orbit coupling in the combination with the Zeeman splitting (ZS). In the ``heavy-atom" approximation, which was previously elaborated for the bosonic system, the usual kinetic energy is neglected, which gives rise to a linear spectrum with a bandgap. The model includes the effective Pauli self-repulsion with power $7/3$, as produced by the density-functional theory of Fermi superfluids. In the general case, the inter-component contact repulsion is included too. We construct a family of gap solitons of the SV type populating the spectral bandgap. A stability region is identified for the SV solitons, by means of systematic simulations, in the parameter plane of the cross-repulsion strength and chemical potential. The stability region agrees with the prediction of the anti-Vakhitov-Kolokolov criterion, which is a relevant necessary stability condition for systems with self-repulsive nonlinearities. We also test the stability of the SV solitons against a sudden change of the ZS strength, which initiates robust oscillations in the spin state of the soliton due to transfer of particles between the system's components.