# Quantum Phases of Matter on a 256-Atom Programmable Quantum Simulator

**Authors:** Sepehr Ebadi, Tout T. Wang, Harry Levine, Alexander Keesling, Giulia Semeghini, Ahmed Omran, Dolev Bluvstein, Rhine Samajdar, Hannes Pichler, Wen Wei Ho, Soonwon Choi, Subir Sachdev, Markus Greiner, Vladan Vuletic, Mikhail D. Lukin  
**arXiv:** [2012.12281](https://arxiv.org/abs/2012.12281)  
**Date:** 2020-12-22  
**Summary page:** https://www.summarizepaper.com/en/paper/2012.12281v1/

## Key points

- Detailed exploration of quantum phases of matter on a 256-atom programmable quantum simulator
- Use of two-dimensional arrays of neutral atoms with strong interactions controlled through coherent atomic excitation into Rydberg states
- Realization of a quantum spin model with adjustable interactions for system sizes ranging from 64 to 256 qubits
- Creation and analysis of high-fidelity antiferromagnetically ordered states and investigation of the universal properties of an Ising quantum phase transition in (2+1) dimensions
- Exploration of new quantum phases emerging from the interplay between interactions and coherent laser excitation
- Experimental mapping of the phase diagram and studying the impact of quantum fluctuations to gain insights into complex quantum matter
- Opening avenues for further research into exotic quantum phases, non-equilibrium entanglement dynamics, and efficient implementation of quantum algorithms
- Enhancement of Rydberg detection fidelity using microwave pulses and defining coarse-grained local staggered magnetization for site analysis to deepen understanding of the system's behavior
- Establishment of a solid foundation for future investigations into advanced quantum phenomena on larger scales involving several hundred qubits

## Summary

In this study, we present a detailed exploration of quantum phases of matter on a 256-atom programmable quantum simulator. Our approach involves using two-dimensional arrays of neutral atoms with strong interactions controlled through coherent atomic excitation into Rydberg states. By implementing this method, we successfully realize a quantum spin model with adjustable interactions for system sizes ranging from 64 to 256 qubits. To validate the system's capabilities, we create and analyze high-fidelity antiferromagnetically ordered states and investigate the universal properties of an Ising quantum phase transition in (2+1) dimensions. Furthermore, we explore various new quantum phases that emerge from the interplay between interactions and coherent laser excitation. Through experimental mapping of the phase diagram and studying the impact of quantum fluctuations, we gain valuable insights into complex quantum matter. Our findings open up avenues for further research into exotic quantum phases, non-equilibrium entanglement dynamics, and efficient implementation of quantum algorithms. By enhancing Rydberg detection fidelity using microwave pulses and defining coarse-grained local staggered magnetization for site analysis, we deepen our understanding of the system's behavior. These experiments lay a solid foundation for future investigations into advanced quantum phenomena on larger scales involving several hundred qubits.