Detector entanglement: Quasidistributions for Bell-state measurements

Abstract

Measurements in the quantum domain can exceed classical notions. This concerns fundamental questions about the nature of the measurement process itself, as well as applications, such as their function as building blocks of quantum information processing protocols. In this paper we explore the notion of entanglement for detection devices in theory and experiment. A method is devised that allows one to determine nonlocal quantum coherence of positive-operator-valued measures via negative contributions in a joint distribution that fully describes the measurement apparatus under study. This approach is then applied to experimental data for detectors that ideally project onto Bell states. In particular, we describe the reconstruction of the aforementioned entanglement quasidistributions from raw data and compare the resulting negativities with those expected from theory. Therefore, our method provides a versatile toolbox for analyzing measurements regarding their quantum-correlation features for quantum science and quantum technology.

version accepted for publication

References in corpus (11)

• Measuring measurement
• A computable measure of nonclassicality for light
• Universal resources for measurement-based quantum computation
• All sets of incompatible measurements give an advantage in quantum state discrimination
• Entanglement swapping and quantum correlations via Elegant Joint Measurements
• Experimental quantification of coherence of a tunable quantum detector
• Relation between Quantum Coherence and Quantum Entanglement in Quantum Measurements
• Experimental entanglement characterization of two-rebit states
• Interpreting quantum coherence through a quantum measurement process
• Compressively certifying quantum measurements
• Directly Characterizing the Coherence of Quantum Detectors by Sequential Measurement

Cited by in corpus (1)

• Activation of entanglement in generalized entanglement swapping