Obtaining Long Coherence Times in a Condensate Interferometer

这个项目的重点是研究玻色-爱因斯坦凝聚体的相干时间，通过开发一种干涉仪设备，能够测量相干时间长达5秒或更长。干涉原子包将被光诱导布拉格衍射分离和重组，并且原子将始终被限制在弱磁阱中。将特别注意相扩散的观察和研究。这种退相干源产生于包中原子之间的相互作用，再加上包中原子数量不可避免的波动。本工作将探索减少相位扩散以获得更长的相干时间的方法，这是具有实际意义的。就更广泛的影响而言，该研究具有社会有用技术创新的潜力，特别是在惯性导航和石油勘探方面。此外，该项目将涉及研究生和本科生的研究培训。

This project focuses on the study of the coherence time of a Bose-Einstein condensate by developing an interferometer apparatus capable of measuring coherence times of up to five seconds or more. The interfering atom packets will be separated and recombined using optically induced Bragg diffraction, and the atoms will be confined at all times in a weak magnetic trap. Special attention will be paid to the observation and investigation of phase diffusion. This source of decoherence arises from the interactions between atoms in a packet, when coupled to the unavoidable fluctuations in the number of atoms in the packet. The work will explore ways in which the phase diffusion can be reduced to obtain longer coherence times, which are of practical interest. On the broader impact, the research has the potential for socially useful technological innovations, in particular for inertial navigation and for oil exploration. In addition, the project will involve research training of graduate and undergraduate students.