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arXiv · 2104.08794

Atom-Orbital Qubits under Holonomic Quantum Control

Abstract

Quantum computing has been attracting tremendous efforts in recent years. One prominent application is to perform quantum simulations of electron correlations in large molecules and solid-state materials, where orbital degrees of freedom are crucial to quantitatively model electronic properties. Electron orbitals unlike quantum spins obey crystal symmetries, making the atomic orbital in optical lattices a natural candidate to emulate electron orbitals. Here, we construct atom-orbital qubits by manipulating $s$- and $d$-orbitals of atomic Bose-Einstein condensation in an optical lattice. Noise-resilient quantum gate operations are achieved by performing holonomic quantum control, which admits geometrical protection. We find it is critical to eliminate the orbital leakage error in the system. The gate robustness is tested by varying the intensity of the laser forming the lattice. Our work opens up wide opportunities for atom-orbital based quantum information processing, of vital importance to programmable quantum simulations of multi-orbital physics in molecules and quantum materials.

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Hongmian Shui, Shengjie Jin, Zhihan Li, Fansu Wei, Xuzong Chen, Xiaopeng Li, Xiaoji Zhou. 2021-12-09. Atom-Orbital Qubits under Holonomic Quantum Control. https://doi.org/10.1103/physreva.104.l060601

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