Abstract
Optical tweezer arrays with neutral atoms have shown their potential as versatile tools for quantum computation and simulation. In this thesis, I present a quantum apparatus based on neutral strontium-88 atoms trapped in an optical tweezer array. We highlight the advantages of optical tweezers in flexibility, scalability, and controllability. The advantages of strontium atoms are also illustrated in cooling, trapping, and imaging processes.
In the first part, we will discuss the design and installation of our apparatus, and the process to obtain ultra-cold strontium samples with a two-stage magneto-optical trap (MOT) technique. We also present technical details on laser frequency stabilization, highprecision alignment of microscope objective systems, and MOT diagnostics and optimization.
The second part of the thesis demonstrates the single-atom optical tweezer arrays of ultra-cold strontium with details of single-atom loading, cooling and high-fidelity imaging. We also discuss the techniques to generate optical tweezers array with high homogeneity with a standard deviation within 2%. Specifically, we developed a novel enhanced-loading method with dual-wavelength tweezers, with which we achieve a 96% loading rate with low laser power consumption and iteration time cost. This method allows extra potentials of the scalability of magic-wavelength tweezers array.
In the third part, we report our simulation of quantum walk in a one-dimensional optical tweezer array. We introduce an approach to enable tunneling with a short tweezer spacing of approximately ∼1μm and demonstrate how this method allows for dynamic control of the experiment. We present tunneling results of the quantum walk under various experimental configurations, along with the characteristic statistics that distinguish quantum behavior from classical random walk.
We conclude this thesis with the outlooks towards clock transition and Rydberg excitations of tweezers-trapped strontium atoms, which may pave the way towards high-fidelity quantum gate operations.