Remote entanglement generation with trapped ions and Greenberger-Horne-Zeilinger (GHZ) entangled states

Long chains of trapped ions represent a leading platform for quantum information processing, yet their scalability is hindered by two significant challenges: spectral crowding and excess motional heating. Addressing these limitations is crucial for advancing large-scale ion trap quantum computing. One promising approach to enhance the computational power of trapped-ion systems is through modular photonic interconnects, enabling entanglement between ions in separate traps. In this poster, we summarize recent advancements on this front. Over the past few years, we have successfully employed polarization-encoded and time-bin-encoded photons to achieve remote entanglement between trapped ¹³⁸Ba⁺ ions, exhibiting the highest ever fidelity and entanglement rate. We also report on our progress in the remote entanglement of qudits and the generation of remote three-qubit Greenberger-Horne-Zeilinger (GHZ) states. This work establishes a foundation for future applications in distributed and modular quantum computing and quantum networking, where long-distance entanglement distribution is essential.