A Clock Laser Proposal for Strontium Tweezers Arrays Experiments Towards Quantum Computations

Tsz Fung Wong

Published Jan 1, 2025• 0 citations

Abstract

Neutral atoms confined in optical dipole traps, commonly referred to as optical tweezers, have attracted significant attention in the fields of quantum simulation and computation. This is attributed to their notable flexibility, relatively long coherence times, and promising scalability when compared to more established physical systems, such as superconducting circuits and trapped ions. This thesis presents a proposal for a clock laser designed to target the 698 nm transition in the bosonic isotope of strontium,88Sr. An overview of the experimental setup, encompassing the apparatus configuration, the generation of optical tweezers, and the laser sequences employed, is provided in the introduction. Following this, the thesis examines mechanisms that facilitate the forbidden clock transition, specifically a two-photon scheme and the magnetic admixture scheme. Additionally, an analytical presentation of the anticipated systematic light shifts is provided, as well as the experimental parameters. The state detection scheme and the associated imaging scheme are presented. The isolation architecture implemented to meet the stringent requirements of the clock laser is described. Followed by a section presenting the design of the optical configuration, the generation of error signals, and the associated feedback loops. As part of this presentation, a concise review of the Pound-Drever-Hall (PDH), fiber noise cancellation (FNC) and optical beating techniques is provided. Finally, the thesis outlines the preliminary scheme of generating Rydberg excitations and it manipulations following the implementation of the clock laser. Furthermore, the thesis notes several ongoing projects, such as the assembly and calibration of an improved spectroscopy cell and an external cavity diode laser (ECDL). Additionally, a concept for incorporating machine learning techniques to improve experimental efficiency is presented prior to the conclusion.

DOI: 10.14711/thesis-hdl151237

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