Measurement induced dynamics and defect stabilization in spinor condensates
Physics and Astronomy
Condensed Matter Physics
Annual Meeting of the American Physical Society Mid-Atlantic Section
College Park, MD
Understanding system-reservoir dynamics in many-body physics is a new frontier. An external environment can be thought of as a 'measurement reservoir' which extracts information about the quantum system. Weak (i.e. minimally destructive) measurements provide a time-resolved but noisy record of system evolution. In this talk, we propose using weak measurement and feedback to probe and manipulate spinor Bose-Einstein condensates, focusing on the trade-off between usable information obtained from measurement and the effect of measurement on the system (quantum backaction). As a prototype example, we consider the dynamics of a domain wall in a two-component BEC and 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.
Hilary Hurst and I. B. Spielman. "Measurement induced dynamics and defect stabilization in spinor condensates" Annual Meeting of the American Physical Society Mid-Atlantic Section (2018).