Emergent classicality in continuous quantum measurements

Abstract

We develop a classical theoretical description for nonlinear many-body dynamics that incorporates the back-action of a continuous measurement process. The classical approach is compared with the exact quantum solution in an example with an atomic Bose-Einstein condensate in a double-well potential where the atom numbers in both potential wells are monitored by light scattering. In the classical description the back-action of the measurements appears as diffusion of the relative phase of the condensates on each side of the trap. When the measurements are frequent enough to resolve the system dynamics, the system behaves classically. This happens even deep in the quantum regime, and demonstrates how classical physics emerges from quantum mechanics as a result of measurement back-action.

References in corpus (7)

• Dynamics and statistical mechanics of ultra-cold Bose gases using c-field techniques
• Classical bifurcation at the transition from Rabi to Josephson dynamics
• Beyond mean-field dynamics of small Bose-Hubbard systems based on the number-conserving phase space approach
• Exact number conserving phase-space dynamics of the M-site Bose-Hubbard model
• Nonlinear Phenomenology from Quantum Mechanics: Soliton in a Lattice
• Number-Phase Wigner Representation for Scalable Stochastic Simulations of Controlled Quantum Systems
• Nonlinearity from quantum mechanics: Dynamically unstable Bose-Einstein condensate in a double-well trap

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• Caustics in quantum many-body dynamics
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• Adiabatic Quantum Zeno Dynamics of Bosonic Atom Pairs with Large Inelastic Losses