Creating full-Bloch Bose–Einstein condensates with Raman q-plates
Creating full-Bloch Bose–Einstein condensates with Raman q-plates
复制标题
使用拉曼 q 板创建全布洛赫玻色-爱因斯坦凝聚态
DOI：
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发表时间：
2016
期刊：
影响因子：
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通讯作者：
N. Bigelow
中科院分区：
文献类型：
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作者：
J. Schultz;A. Hansen;Joseph D. Murphree;M. Jayaseelan;N. Bigelow
赝自旋1/2玻色-爱因斯坦凝聚体（BEC）中的相干双光子光学拉曼相互作用充当原子的q板，将自旋转换为轨道角动量。该拉曼q板在其偏振分布中具有奇异图案，类似于奇异光学中使用的奇异双折射q板。BEC涡旋的缠绕方向和大小以及最终的自旋态取决于拉曼q板光束的初始自旋态和拓扑结构。利用奇异光学的数学和几何基础，我们推导出这个拉曼q板的等效琼斯矩阵，并使用它来创建和表征原子自旋奇异性的BEC是类似于光学C点奇异性的偏振。通过调节光学拉曼参数，我们可以得到一个包含了两态系统中所有可能叠加态的无核涡旋自旋织构。我们确定这种自旋纹理作为一个完整的布洛赫BEC，因为布洛赫球上的每一个点都表示在原子云的横截面中的某个点。这种自旋-轨道相互作用及其产生的自旋纹理可能允许观察物质波中有趣的几何相位，并导致使用旋量BEC进行拓扑量子计算的方案。
A coherent two-photon optical Raman interaction in a pseudo-spin-1/2 Bose–Einstein condensate (BEC) serves as a q-plate for atoms, converting spin to orbital angular momentum. This Raman q-plate has a singular pattern in its polarization distribution in analogy to the singular birefringent q-plates used in singular optics. The vortex winding direction and magnitude as well as the final spin state of the BEC depend on the initial spin state and the topology of the optical Raman q-plate beams. Drawing on the mathematical and geometric foundations of singular optics, we derive the equivalent Jones matrix for this Raman q-plate and use it to create and characterize atomic spin singularities in the BEC that are analogous to optical C-point singularities in polarization. By tuning the optical Raman parameters, we can generate a coreless vortex spin texture which contains every possible superposition in a two-state system. We identify this spin texture as a full-Bloch BEC since every point on the Bloch sphere is represented at some point in the cross section of the atomic cloud. This spin–orbit interaction and the spin textures it generates may allow for the observation of interesting geometric phases in matter waves and lead to schemes for topological quantum computation with spinor BECs.
影响因子：
56.9
作者：
Romming, Niklas;Hanneken, Christian;Wiesendanger, Roland
通讯作者：
Wiesendanger, Roland