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arXiv · 1607.03001

Tomography and Purification of the Temporal-Mode Structure of Quantum Light

Vahid Ansari·John M. Donohue·Markus Allgaier·Linda Sansoni·Benjamin Brecht·Jonathan Roslund·Nicolas Treps·Georg Harder·Christine Silberhorn
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Abstract

High-dimensional quantum information processing promises capabilities beyond the current state of the art, but addressing individual information-carrying modes presents a significant experimental challenge. Here we demonstrate effective high-dimensional operations in the time-frequency domain of non-classical light. We generate heralded photons with tailored temporal-mode structures through ultrafast pulse shaping of a parametric downconversion pump. We then implement a quantum pulse gate, enabled by dispersion-engineered sum-frequency generation, to project onto programmable temporal modes, reconstructing the quantum state in seven dimensions. We also manipulate the time-frequency structure by selectively removing temporal modes, explicitly demonstrating the effectiveness of engineered nonlinear processes for mode-selective manipulation of quantum states.

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Vahid Ansari, John M. Donohue, Markus Allgaier, Linda Sansoni, Benjamin Brecht, Jonathan Roslund, Nicolas Treps, Georg Harder, Christine Silberhorn. 2016-07-11. Tomography and Purification of the Temporal-Mode Structure of Quantum Light. https://doi.org/10.1103/physrevlett.120.213601

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