Weak-measurement-induced phases and dephasing: broken symmetry of the geometric phase

Abstract

Coherent steering of a quantum state, induced by a sequence of weak measurements, has become an active area of theoretical and experimental study. For a closed steered trajectory, the underlying phase factors involve both geometrical and dynamical terms. Furthermore, considering the reversal of the order of the measurement sequence, such a phase comprises a symmetric and an antisymmetric term. Superseding common wisdom, we show that the symmetric and the antisymmetric components do not correspond to the dynamical and geometrical parts respectively. Addressing a broad class of measurement protocols, we further investigate the dependence of the induced phases on the measurement parameters (e.g., the measurement strength). We find transitions between different topologically distinct sectors, defined by integer-valued winding numbers, and show that the transitions are accompanied by diverging dephasing. We propose experimental protocols to observe these effects.

22 pages, 15 figures. Comments are welcome

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Cited by in corpus (7)

• Generalized quantum measurements with matrix product states: Entanglement phase transition and clusterization
• Observing a Topological Transition in Weak-Measurement-Induced Geometric Phases
• Driving quantum systems with repeated conditional measurements
• Weak-measurement-induced asymmetric dephasing: manifestation of intrinsic measurement chirality
• Topological transitions of the generalized Pancharatnam-Berry phase
• Geometric phases along quantum trajectories
• How pure can we go with adiabatic state manipulation?