Design of a high numerical aperture vacuum chamber for 3D optical lattice experiments

Singh, Bhagwan

Published Apr 21, 2022• 0 citations

Abstract

The next generation of 3D optical lattice experiments requires a new vacuum chamber design. In the past, a 3D optical lattice apparatus in our lab was used to create and observe antiferromagnetic (AFM) coorelations within a 6Li-based degenerate Fermi gas. In that experiment, implementing anti-trapping beams overlapped with the standard lattice beams allowed the potential landscape to be made smoother, in an effort to increase the spatial extent of the AFM phase. Nevertheless, preparing atoms to be even cooler, and further extending the region of interest requires newer solutions. One method is to use the anti-trapping beams in a slightly different manner. By utilizing a higher numerical aperture optical beam line for anti-trapping, finer adjustments can be made in the potential. Combined with digital-micromirror based holography techniques. the anti-trapping beams can be custom-shaped to carve even finer details into the optical lattice. With sufficient control over beamshaping, one could perform better entropy re-distribution within the atom cloud. In this way, the central AFM region can be made colder by pushing entropy out to the wings. In this thesis, I will detail the work done in analyzing and designing a new chamber to fulfill the previously mentioned features.

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