Chip-Scale Laser-Cooling Atoms based on Diffractive Optical Elements
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摘要: 冷原子系统为量子精密测量过程提供了一种接近于静止的测量介质,从而避免了热原子工作介质中存在的频移和展宽,使得测量结果更加精确。但是目前量子精密测量系统中原子冷却部分体积庞大、结构复杂,不利于实现可分发量子计量标准系统的小型化。为了解决现有磁光阱系统复杂的问题,采取衍射光栅芯片与原子冷却俘获相结合的方案,通过线性光栅对单束入射光波进行相位调制,成功实现芯片尺度下原子的冷却。微小型化磁光阱核心芯片的制备,搭建了光学结构简单的磁光阱系统,为未来进一步实现磁光阱整体系统微小型化奠定了坚实基础。Abstract: Cold-atom systems provide a nearly static measurement medium with almost no interaction between the atoms for quantum precision measurement processes, thereby avoiding the frequency shift and broadening existing in the working medium of hot atoms, making the measurement results more accurate. However, the atomic cooling part of current quantum precision measurement systems is bulky and complex, which is not conducive to miniaturization of distributable quantum measurement standard systems. In order to make a less complex magneto-optical trap system, we adopted the scheme to combine the diffraction grating chip and the atomic cooling technique. The wavefront of a single incident light was phase modulated through the linear grating, and the atoms were successfully trapped on a chip scale. The preparation of the core chip of a miniaturized magneto-optical trap and the realization of the magneto-optical trap system with a simple optical structure can lay a solid foundation for further miniaturization of the overall system of a magneto-optical trap in the future.
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Key words:
- grating /
- magneto-optical trap /
- miniaturization /
- nano lithography
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表 1 光栅芯片衍射角及衍射效率测量结果
Table 1. Measurement results of the diffraction angle and efficiency of the grating chip
光栅区域 1 2 3 衍射角θ 34.8° 34.5° 34.3° 衍射效率η 43.5% 41.1% 42.2% -
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