Quasiprobability distributions with weak measurements

• URL: http://arxiv.org/abs/2406.06713v2
• Date: Fri, 25 Jul 2025 14:36:18 GMT
• Title: Quasiprobability distributions with weak measurements
• Authors: Gabriele Bizzarri, Stefano Gherardini, Mylenne Manrique, Fabio Bruni, Ilaria Gianani, Marco Barbieri,
• Abstract summary: We discuss and experimentally demonstrate the role of quantum coherence in a sequence of two measurements collected at different times using weak measurements.<n>We determine the quasiprobability distributions associated to this procedure using both the commensurate and the Margenau-Hill quasiprobabilities approaches.<n>Our results show how quasidistributions may find application in inspecting quantum monitoring, when part of the initial quantum coherence needs to be preserved.
• Score: 0.20616237122336117
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We discuss and experimentally demonstrate the role of quantum coherence in a sequence of two measurements collected at different times using weak measurements. For this purpose, we have realized a weak-sequential measurement protocol with photonic qubits, where the first measurement is carried out as a positive operator-valued measure, whereas the second one is a projective operation. We determine the quasiprobability distributions associated to this procedure using both the commensurate and the Margenau-Hill quasiprobabilities approaches. By tuning the weak measurements, we obtain a quasidistribution that may or may not exhibit negative parts, depending on the suitability of a contextual model for describing the experiment. Our results show how quasidistributions may find application in inspecting quantum monitoring, when part of the initial quantum coherence needs to be preserved.

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