Pugatch R, Shuker M, Firstenberg O, Ron A, Davidson N
Department of Physics of Complex Systems, Weizmann Institute of Science, Rehovot 76100, Israel.
Phys Rev Lett. 2007 May 18;98(20):203601. doi: 10.1103/PhysRevLett.98.203601. Epub 2007 May 14.
We report an experiment in which an optical vortex is stored in a vapor of Rb atoms. Because of its 2pi phase twist, this mode, also known as the Laguerre-Gauss mode, is topologically stable and cannot unwind even under conditions of strong diffusion. For comparison, we stored a Gaussian beam with a dark center and a uniform phase. Contrary to the optical vortex, which stays stable for over 100 micros, the dark center in the retrieved flat-phased image was filled with light after a storage time as short as 10 micros. The experiment proves that higher electromagnetic modes can be converted into atomic coherences and that modes with phase singularities are robust to decoherence effects such as diffusion. This opens the possibility to more elaborate schemes for classical and quantum information storage in atomic vapors.
我们报告了一项实验，其中一个光学涡旋被存储在铷原子蒸汽中。由于其2π相位扭曲，这种模式，也称为拉盖尔 - 高斯模式，在拓扑结构上是稳定的，即使在强扩散条件下也不会解缠。作为对比，我们存储了一个中心为暗区且相位均匀的高斯光束。与能稳定存在超过100微秒的光学涡旋相反，在仅10微秒的存储时间后，恢复的平相图像中的暗中心就被光填满了。该实验证明了更高阶的电磁模式可以转化为原子相干性，并且具有相位奇点的模式对诸如扩散等退相干效应具有鲁棒性。这为在原子蒸汽中进行更精细的经典和量子信息存储方案开辟了可能性。
