Trapped ion systems are a leading platform for quantum simulation of spin models. Current experiments are limited to less than 55 ions due to collisions with background gas that destroy the ion crystal. Here, we present a novel cryogenic ion trapping system  designed for large scale quantum simulation of spin models. The apparatus is a segmented blade trap enclosed in a 4 K cryostat, which enables us to routinely trap above 100 171Yb ions in a linear configuration with an ion chain lifetime more than four hours due to a low background pressure from differential cryo-pumping. With these improvements, we are moving forward to perform large scale quantum simulation of spin models that will challenge classical simulators. In this cryogenic trapped ion setup, we are working on Confinement  and Quantum Approximate Optimization Algorithm (QAOA)  experiments with ion chain larger than 20 ions.
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Wen Lin Tan is a third year grad student from Chris Monroe's Trapped Ion Quantum Information group at University of Maryland, College Park. I did my undergr aduate at University of Washington, Seattle, where I worked on trapped ions under Prof. Boris Blinov. My research interest is Large Scale Quantum Simulation using Trapped Ions. I spend two years of my grad school building a cr yogenic trapped ion system. Now, we are starting to do Quantum Simulation in this system.