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arXiv · 1406.5821

State selective detection of hyperfine qubits

Sabine Wölk·Christian Piltz·Theeraphot Sriarunothai·Christof Wunderlich
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Abstract

In order to faithfully detect the state of an individual two-state quantum system (qubit) realized using, for example, a trapped ion or atom, state selective scattering of resonance fluorescence is well established. The simplest way to read out this measurement and assign a state is the threshold method. The detection error can be decreased by using more advanced detection methods like the time-resolved method or the $π$-pulse detection method. These methods were introduced to qubits with a single possible state change during the measurement process. However, there exist many qubits like the hyperfine qubit of $^{171}Yb^+$ where several state change are possible. To decrease the detection error for such qubits, we develope generalizations of the time-resolved method and the $π$-pulse detection method for such qubits. We show the advantages of these generalized detection methods in numerical simulations and experiments using the hyperfine qubit of $^{171}Yb^+$. The generalized detection methods developed here can be implemented in an efficient way such that experimental real time state discrimination with improved fidelity is possible.

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Sabine Wölk, Christian Piltz, Theeraphot Sriarunothai, Christof Wunderlich. 2014-06-23. State selective detection of hyperfine qubits. https://doi.org/10.1088/0953-4075%2F48%2F7%2F075101

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