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arXiv · 2003.11981

Tomography of time-bin quantum states using time-resolved detection

Karolina Sedziak-Kacprowicz·Artur Czerwinski·Piotr Kolenderski
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Abstract

We present a method for measuring quantum states encoded in the temporal modes of photons. The basis for the multilevel quantum states is defined by the use of modes propagating in a dispersive medium, which is a fiber in this case. The propagation and time-resolved single photon detection allow us to define a positive-operator valued measure (POVM). The POVM depends on the amount of dispersion and the characteristics of a detector. This framework is numerically tested by performing quantum state tomography on a large number of states for a set of realistic experimental settings. Finally, the average fidelity between the expected and reconstructed states is computed for qubits, qutrits and entangled qubits.

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Karolina Sedziak-Kacprowicz, Artur Czerwinski, Piotr Kolenderski. 2020-11-24. Tomography of time-bin quantum states using time-resolved detection. https://doi.org/10.1103/physreva.102.052420

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