Events

Past Event

Physics Colloquium: "Entangling Ultracold Molecules" with Kang-Kuen Ni (Harvard University)

November 10, 2025
12:30 PM - 1:30 PM
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Theory Center (Pupin 8th Floor)

"Entangling Ultracold Molecules"

Coherence and entanglement are key features of quantum mechanics, although they are susceptible to environmental perturbations. A conventional strategy to entangle qubits with high fidelity is to leverage precisely controlled interactions while keeping qubits from decohering. By leveraging electric dipolar interactions, I will report entangling individual trapped NaCs molecules in optical tweezers and realizing a quantum logic gate with trapped molecules[1]. Going beyond this paradigm, we explore and ask the question: Can coherence be preserved during chemical reactions and subsequently harnessed to produce entangled products? To address this question, we conduct investigations within the context of an atom-exchange chemical reaction (2KRb -> K2 + Rb2) at a temperature of 500nK[2]. I will share our research findings including surprises and puzzles. 

[1] Entanglement and iSWAP gate between molecular qubits, Nature 637, 821 (2025)

[2] Quantum interference in atom-exchange reactions, Science 384, 1117 (2024)

Research Overview