光晶格中的量子液滴的变分动力学分析
Analysis of Variational Dynamics of Quantum Droplets in Optical Lattices
DOI: 10.12677/app.2024.145035, PDF,   
作者: 田 尚:浙江师范大学物理与电子信息工程学院,浙江 金华
关键词: 玻色–爱因斯坦凝聚量子液滴光晶格拉格朗日变分法Bose-Einstein Quantum Droplet Optical Lattice Lagrange Variational Method
摘要: 本文研究了光晶格中量子液滴的波包动力学以及动力学不稳定性。我们从光晶格中量子液滴的Gross-Pitaevskii方程出发,通过紧束缚近似得到对应的离散方程,随后通过拉格朗日变分法对量子液滴进行动力学分析,并且通过元激发谱对量子液滴进行动力学不稳定性分析。结果表明,随着量子液滴相互作用强度的增强,波包的自束缚区域逐渐缩小,扩散区域逐渐增大,并且当液滴相互作用强度达到某一临界值时,原本存在的稳定振荡区域完全消失。通过光晶格中量子液滴的元激发谱可以发现,液滴相互作用强度发生微小的变化动力学不稳定性会发生显著变化,并且随着液滴相互作用强度的减小,动力学不稳定性区域逐渐收缩至准动量较小的区域。
Abstract: This article investigates the wave packet dynamics and dynamic instability of quantum droplets in optical lattices. Starting from the Gross-Pitaevskii equation for quantum droplets in optical lattices, we obtain the corresponding discrete equations through the tight-binding approximation. Subsequently, the dynamics of quantum droplets are analyzed using the Lagrangian variational method, and the dynamic instability is analyzed through the elementary excitation spectrum. The results indicate that as the interaction strength of quantum droplets increases, the self-trapped region of the wave packet gradually shrinks, while the diffusive region gradually expands. Furthermore, when the interaction strength of the droplets reaches a certain critical value, the originally stable oscillation region completely disappears. Through the elementary excitation spectrum of quantum droplets in optical lattices, it can be observed that minor changes in the interaction strength of the droplets lead to significant changes in dynamic instability. Additionally, as the interaction strength of the droplets decreases, the region of dynamic instability gradually contracts to areas with smaller quasi-momentum.
文章引用:田尚. 光晶格中的量子液滴的变分动力学分析[J]. 应用物理, 2024, 14(5): 301-308. https://doi.org/10.12677/app.2024.145035

参考文献

[1] Xu, Y., Zhang, Y.P. and Wu, B. (2013) Bright Solitons in Spin-Orbit-Coupled Bose-Einstein Condensates. Physical Review A, 87, Article ID: 013614. [Google Scholar] [CrossRef
[2] Han, W., Zhang, X.F., Wang, D.S., et al. (2018) Chiral Supersolid in Spin-Orbit-Coupled Bose Gases with Soft-Core Long-Range Interactions. Physical Review Letters, 121, Article ID: 030404. [Google Scholar] [CrossRef
[3] Wang, L.X., Dai, C.Q., Wen, L., et al. (2018) Dynamics of Vortices Followed by the Collapse of Ring Dark Solitons in a Two-Component Bose-Einstein Condensate. Physical Review A, 97, Article ID: 063607. [Google Scholar] [CrossRef
[4] Petrov, D.S. (2015) Quantum Mechanical Stabilization of a Collapsing Bose­Bose Mixture. Physical Review Letters, 115, Article ID: 155302. [Google Scholar] [CrossRef
[5] Segev, M., Valley, G.C., Crosignani, B., et al. (1994) Steady-State Spatial Screening Solitons in Photorefractive Materials with Anexternal Applied Field. Physical Review Letters, 73, Article ID: 3211. [Google Scholar] [CrossRef
[6] Huang, J.S., Jiang, X.D., Chen, H.Y., et al. (2015) Quadrupolar Matter-Wave Soliton in Two-Dimensional Free Space. Frontiers of Physics, 10, 1-7. [Google Scholar] [CrossRef
[7] Wang, Y.Y., Liang, C., Dai, C.Q., et al. (2017) Exact Vector Multipole and Vortex Solitons in the Media with Spatially Modulatedcubic-Quintic Nonlinearity. Nonlinear Dynamics, 90, 1269-1275. [Google Scholar] [CrossRef
[8] Dai, C.Q., Chen, R.P., Wang, Y.Y., et al. (2017) Dynamics of Light Bullets in Inhomogeneous Cubic-Quintic-Septimal Nonlinear Mediawith PT-Symmetric Potentials. Nonlinear Dynamics, 87, 1675-1683. [Google Scholar] [CrossRef
[9] Chen, X.W., Deng, Z.G., Xu, X.X., et al. (2020) Nonlinear Modes in Spatially Confined Spin-Orbit-Coupled Bose-Einstein Condensates with Repulsive Nonlinearity. Nonlinear Dynamics, 101, 569-579. [Google Scholar] [CrossRef
[10] Ye, Z.J., Chen, Y.X., Zheng, Y.Y., et al. (2020) Symmetry Breaking of a Matter-Wave Soliton in a Double-Well Potential Formed by Spatially Confined Spin-Orbit Coupling. Chaos, Solitons & Fractals, 130, Article ID: 109418. [Google Scholar] [CrossRef
[11] Li, Y.Y., Luo, Z.H., Liu, Y., et al. (2017) Two-Dimensional Solitons and Quantum Droplets Supported by Competing Self-And Cross-Interactions in Spin-Orbit-Coupled Condensates. New Journal of Physics, 19, Article ID: 113043. [Google Scholar] [CrossRef
[12] Lee, T.D., Huang, K. and Yang, C.N. (1957) Eigenvalues and Eigenfunctions of a Bose System of Hard Spheres and Its Low-Temperature Properties. Physical Review, 106, 1135-1145. [Google Scholar] [CrossRef
[13] Schmitt, M., Wenzel, M., Boettcher, F., et al. (2016) Self-Bound Droplets of a Dilute Magnetic Quantum Liquid. Nature, 539, 259-262. [Google Scholar] [CrossRef] [PubMed]
[14] Cabrera, C.R., Tanzi, L., Sanz, J., et al. (2017) Quantum Liquid Droplets in a Mixture of Bose-Einstein Condensates. Science, 359, 301-304. [Google Scholar] [CrossRef] [PubMed]
[15] Tylutki, M., Astrakharchik, G.E., Malomed, B.A., et al. (2020) Collective Excitations of a One-Dimensional Quantum Droplet. Physical Review A, 101, Article ID: 051601. [Google Scholar] [CrossRef
[16] Luo, Z.H., Pang, W., Liu, B., et al. (2021) A New Form of Liquid Matter: Quantum Droplets. Frontiers of Physics, 16, Article No. 32201. [Google Scholar] [CrossRef
[17] Liu, B., Zhang, H.F., Zhong, R.X., et al. (2019) Symmetry Breaking of Quantum Droplets in a Dual-Core Trap. Physical Review A, 99, Article ID: 053602. [Google Scholar] [CrossRef
[18] Guo, Z.C., Jia, F., Li, L.T., et al. (2021) Lee-Huang-Yang Effects in the Ultracold Mixture of 23Na and 87Rb with Attractive Interspecies Interactions. Physical Review Research, 3, Article ID: 033247. [Google Scholar] [CrossRef
[19] Zhou, Z., Yu, X., Zou, Y., et al. (2019) Dynamics of Quantum Droplets in a One-Dimensional Optical Lattice. Communications in Nonlinear Science and Numerical Simulation, 78, Article ID: 104881. [Google Scholar] [CrossRef
[20] Dong, L.W., Qi, W., Peng, P., et al. (2020) Multi-Stable Quantum Droplets in Optical Lattices. Nonlinear Dynamics, 102, 303-310. [Google Scholar] [CrossRef
[21] Zheng, Y.Y., Chen, S.T., Huang, Z.P., et al. (2021) Quantum Droplets in Two-Dimensional Optical Lattices. Frontiers of Physics, 16, Article No. 22501. [Google Scholar] [CrossRef
[22] Trombettoni, A. and Smerzi, A. (2001) Discrete Solitons and Breathers with Dilute Bose-Einstein Condensates. Physical Review Letters, 86, Article ID: 2353. [Google Scholar] [CrossRef