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arXiv · 1809.08257

Measurement induced dynamics and stabilization of spinor condensate domain walls

Hilary M. Hurst·I. B. Spielman
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Abstract

Weakly measuring many-body systems and allowing for feedback in real-time can simultaneously create and measure new phenomena in strongly correlated quantum systems. We study the dynamics of a continuously measured two-component Bose-Einstein condensate (BEC) potentially containing a domain wall, and focus on the trade-off between usable information obtained from measurement and quantum backaction. Each weakly measured system yields a measurement record from which we extract real-time dynamics of the domain wall. We show that quantum backaction due to measurement causes two primary effects: domain wall diffusion and overall heating. The system dynamics and signal-to-noise ratio depend on the choice of measurement observable. We describe a feedback protocol to create and stabilize a domain wall in the regime where domain walls are unstable, giving a prototype example of Hamiltonian engineering using measurement and feedback.

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Hilary M. Hurst, I. B. Spielman. 2019-04-26. Measurement induced dynamics and stabilization of spinor condensate domain walls. https://doi.org/10.1103/physreva.99.053612

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