Journal of Physics B Atomic Molecular and Optical Physics

Unsharp measurements using trapped ytterbium ions: a feasibility study

Siann Bester, Thomas Konrad, Naleli Jubert Matjelo, Christine M. Steenkamp

Published Jul 28, 2026• 0 citations

Abstract

Abstract Numerical simulations are used to study unsharp measurements in a system of trapped ytterbium ions to monitor resonantly driven Rabi oscillations of a target ion by weak coupling to an auxiliary ion. The simulation combines the positive operator-valued measure formalism and optical Bloch equations to model the state of the target ion during the implementation of the unsharp measurement protocol. State monitoring is done using an estimation scheme that is updated with the unsharp measurement results. The model expands on previous work by explicitly including spontaneous emission into the calculations. We propose a method to determine convergence of the estimation scheme, useful in an experimental setting, which does not rely on using the target state. The simulation results show the feasibility conditions for implementing unsharp measurements experimentally and demonstrate the robustness of the estimation scheme in the presence of experimental noise and when the qubit Rabi frequency is not precisely known. We find that the timescale of transitions that change the motional state is the main technical challenge for experimental implementation.

DOI: 10.1088/1361-6455/ae91b0

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