A motorized rotation mount for the switching of an optical beam path in under 20 ms using polarization control

Raghuram, Adarsh P.; Mortlock, Jonathan M.; Bromley, Sarah L.; Cornish, Simon L.

Abstract

We present a simple motorized rotation mount for a half-wave plate that can be used to rapidly change the polarization of light. We use the device to switch a high power laser beam between different optical dipole traps in an ultracold atom experiment. The device uses a stepper motor with a hollow shaft, which allows a beam to propagate along the axis of the motor shaft, minimizing inertia and mechanical complexity. A simple machined adapter is used to mount the wave plate. We characterize the performance of the device, focusing on its capability to switch a beam between the output ports of a polarizing beam splitter cube. We demonstrate a switching time of 15.9(3) ms, limited by the torque of the motor. The mount has a reaction time of 0.52(3) ms and a rotational resolution of 0.45(4)°. The rotation is highly reproducible, with the stepper motor not missing a step in 2000 repeated tests over 11 h.

Citation

Raghuram, A. P., Mortlock, J. M., Bromley, S. L., & Cornish, S. L. (2023). A motorized rotation mount for the switching of an optical beam path in under 20 ms using polarization control. Review of Scientific Instruments, 94(6), https://doi.org/10.1063/5.0139647

• Journal Article Type: Article
• Acceptance Date: May 14, 2023
• Online Publication Date: Jun 1, 2023
• Publication Date: Jun 1, 2023
• Deposit Date: Aug 17, 2023
• Publicly Available Date: Aug 17, 2023
• Journal: Review of Scientific Instruments
• Print ISSN: 0034-6748
• Electronic ISSN: 1089-7623
• Publisher: American Institute of Physics
• Peer Reviewed: Peer Reviewed
• Volume: 94
• Issue: 6
• DOI: https://doi.org/10.1063/5.0139647
• Keywords: Instrumentation
• Public URL: https://durham-repository.worktribe.com/output/1720182