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arXiv · 1406.4049

Quantum interference in the absorption and emission of single photons by a single ion

Michael Schug·Christoph Kurz·Pascal Eich·Jan Huwer·Philipp Müller·Jürgen Eschner
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Abstract

We investigate quantum beats in the arrival-time distribution of single photons from a single trapped $^{40}$Ca$^+$ ion, revealing their fundamentally different physical origins in two distinct experimental situations: In a $Λ$-type level scheme the interference of two 854-nm absorption amplitudes suppresses and enhances the emission process of Raman-scattered 393-nm photons; in a V-type level scheme the interference of two 393-nm emission amplitudes causes a rotation of their dipole emission pattern resulting in a temporal modulation of the detected photons. For both cases we demonstrate coherent control over the quantum-beat phase through the phases of the atomic and photonic input states, which also allows controlled adjustment of the total photon detection efficiency.

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Michael Schug, Christoph Kurz, Pascal Eich, Jan Huwer, Philipp Müller, Jürgen Eschner. 2014-08-18. Quantum interference in the absorption and emission of single photons by a single ion. https://doi.org/10.1103/physreva.90.023829

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