ICFO-Institut de Ciencies Fotoniques, Mediterranean Technology Park, 08860 Castelldefels (Barcelona), Spain.
Phys Rev Lett. 2012 Sep 7;109(10):103603. doi: 10.1103/PhysRevLett.109.103603.
We optically trap a single nanoparticle in high vacuum and cool its three spatial degrees of freedom by means of active parametric feedback. Using a single laser beam for both trapping and cooling we demonstrate a temperature compression ratio of four orders of magnitude. The absence of a clamping mechanism provides robust decoupling from the heat bath and eliminates the requirement of cryogenic precooling. The small size and mass of the nanoparticle yield high resonance frequencies and high quality factors along with low recoil heating, which are essential conditions for ground state cooling and for low decoherence. The trapping and cooling scheme presented here opens new routes for testing quantum mechanics with mesoscopic objects and for ultrasensitive metrology and sensing.
我们在高真空环境中用光阱捕获单个纳米粒子，并通过主动参数反馈冷却其三个空间自由度。我们使用单个激光束同时进行捕获和冷却，实现了四个数量级的温度压缩比。由于没有夹持机构，因此与热浴实现了稳健的解耦，并且无需低温预冷。纳米粒子的尺寸小、质量轻，产生了高的共振频率和高品质因数，同时加热回溅也较低，这是实现基态冷却和低退相干的必要条件。本文提出的捕获和冷却方案为利用介观物体进行量子力学测试以及超高灵敏计量和传感开辟了新途径。
