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arXiv · 2605.29825

Indistinguishability of photonic qubits emitted from trapped $^{40}$Ca$^+$ ions via pulsed excitation

Pascal Baumgart·Max Bergerhoff·Jonas Meiers·Stephan Kucera·Jürgen Eschner
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Abstract

We investigate the indistinguishability of Raman photons generated from two trapped $^{40}$Ca$^+$ ions using few-nanosecond excitation pulses. We elucidate how spontaneous scattering back to the initial state affects Hong-Ou-Mandel interference. We identify the mean number of back-decays as a measurable single-emitter quantity that correlates with achievable interference visibility of photons from two identical emitters.

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Pascal Baumgart, Max Bergerhoff, Jonas Meiers, Stephan Kucera, Jürgen Eschner. 2026-05-28. Indistinguishability of photonic qubits emitted from trapped $^{40}$Ca$^+$ ions via pulsed excitation. https://arxiv.org/abs/2605.29825

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