Quantum Science Seminar

Quantum Processors and Quantum Networks Atom-by-Atom

Hannes Bernien

Hanes Bernien, Associate Professor of Molecular Engineering in the Pritzker School of Molecular Engineering at the University of Chicago, will be presenting “Quantum Processors and Quantum Networks Atom-by-Atom” as part of the Midwest Quantum Collaboratory’s 2023-24 seminar series from 10:30 – 11:30 am on March 28, 2024 in the Phoenix Room in MMPP. A Zoom option is also provided.

Session Abstract:
Reconfigurable arrays of neutral atoms are an exciting platform to study quantum many-body phenomena and quantum information protocols. Their excellent coherence combined with programmable Rydberg interactions have led to intriguing observations such as quantum phase transitions, the discovery of quantum many-body scars, and novel quantum computing architectures.

Here, I will introduce new methods for controlling and measuring atom arrays that open up compelling directions in quantum state control, quantum feedback and many-body physics. First, I will introduce a dual-species atomic array in which the second atomic species can be used to measure and control the primary species. We use an array of cesium qubits to correct correlated phase errors on an array of rubidium data qubits [1]. Rydberg interactions between the two species lead to novel regimes, including greatly enhanced resonant dipole interactions, that we use to demonstrate a 2-qubit gate and quantum non-demolition readout [2].

An alternative, hybrid approach for engineering interactions and scaling these quantum systems is the coupling of atoms to nanophotonic structures in which photons mediate interactions between atoms. Such a system can function as the building block of a large-scale quantum network. In this context, I will present quantum network node architectures that are capable of long-distance entanglement distribution at telecom wavelengths [3] and show how to combine atom-array capabilities with large photonic chips [4].

[1] Singh, Bradley, Anand, Ramesh, White, Bernien, Science 380, 1265 (2023)
[2] Anand, Bradley, White, Ramesh, Singh, Bernien, arXiv:2401.10325 (2024)
[3] Menon, Singh, Borregaard, Bernien NJP 22, 073033 (2020)
[4] Menon, Glachman, Pompili, Dibos, Bernien, arXiv:2311.02153 (2023)