Quantum atom optics with Bose-Einstein condensate atoms

在本课题中，我们利用超冷原子和玻色-爱因斯坦凝聚原子对原子光学进行了研究。首先，我们开发了一种基于原子芯片技术的多功能BEC机。利用该装置，我们可以在3 s内实现87Rb BEC原子的快速生成。接下来，我们研究了在原子芯片上使用BEC原子的原子干涉仪。我们已经实现了长达50 ms的长相干时间和约30%的高干涉条纹对比度。我们还研究了脉冲光驻波势下的BEC原子，即原子光学量子踢转子系统。利用该系统，我们实现了踢脚BEC原子的整流动量输运。我们发现观测到的原子定向输运是由物质波的量子力学干涉引起的。为了研究量子原子光学，我们研制了一种单原子操纵实验装置。我们可以在光学偶极子阱中捕获一个Rb原子超过1s。我们还证明了被困Rb原子激发到高激发态以增强原子-原子相互作用。利用这些方法，我们将能够实现原子之间的量子力学关联或原子的纠缠态。

In this research project, we have studied the atom optics using ultra cold atoms and Bose-Einstein condensate atoms. First we have developed a versatile BEC machine based on an atom chip technology. Using this apparatus, we can realize a fast production of 87Rb BEC atoms within 3 s. Next we have studied the atom interferometer using BEC atoms on an atom chip. We have realized a long coherence time of up to 50 ms with a high interference fringe contrast of about 30%. We have also studied BEC atoms in pulsed optical standing wave potential, so called an atom optics quantum kicked rotor system. Using this system, we have realized a rectified momentum transport for a kicked BEC atoms. We found that the observed directed transport of atoms is caused by the quantum mechanical interference of matter waves. In order to study the quantum atom optics, we have developed an experimental apparatus for the manipulation of a single atom. We could trap a single Rb atom in an optical dipole trap for more than 1 s. We also demonstrated the excitation of trapped Rb atoms to the highly excited Rydberg state to enhance the atom-atom interaction. Using these methods, we will be able to realize a quantum mechanical correlation between atoms or an entangled state of atoms.