Arbitrary optical potentials

• Main Author: Gan, Koon Siang
• Other Authors: Rainer Helmut Dumke
• Format: Final Year Project
• Language: English
• Published: 2014
• Subjects: DRNTU::Science::Physics::Optics and light
• Online Access: http://hdl.handle.net/10356/60810
• Institution: Nanyang Technological University

Here we demonstrate a self-correcting closed loop feedback system for the generation of phase holograms (kinoforms). We investigate the effectiveness of such a system for the production of smooth optical potentials for cold atom experiments. Our algorithm is derived from the Mixed Region Amplitude Freedom (MRAF) algorithm which solves the problem of obtaining a desired target intensity distribution from an initial Gaussian beam. However, the MRAF assumes an ideal optical system. Experimental imperfections are accounted for by imaging the target intensity distribution in a test-setup via a CCD camera and by using this information in a corrective feedback loop. A ring structure was chosen as a test intensity distribution. Three modifications to the original MRAF algorithm are evaluated. Additionally, performance indicators were defined to assess the quality of the produced optical potential. Initial results show that closed-loop feedback systems have the potential to mitigate experimental imperfections however more research into corrective algorithms needs to be carried out.