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Updated: Aug 11, 2026

Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
Emergence of chaos in quantum systems far from the classical limit
Salman Habib1, Kurt Jacobs, Kosuke Shizume
1MS B285, Theoretical Division, The University of California, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
Abstract:
The dynamical status of isolated quantum systems is unclear as conventional measures fail to detect chaos in such systems. However, when quantum systems are subjected to observation--as all experimental systems must be--their dynamics is no longer linear and, in the appropriate limit(s), the evolution of expectation values, conditioned on the observations, closely approaches the behavior of classical trajectories. Here we show, by analyzing a specific example, that microscopic continuously observed quantum systems, even far from any classical limit, can have a positive Lyapunov exponent, and thus be truly chaotic.
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