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arXiv · 2306.04103

Single-qubit measurement of two-qubit entanglement in generalized Werner states

Salini Rajeev·Mayukh Lahiri
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Abstract

Conventional methods of measuring entanglement in a two-qubit photonic mixed state require the detection of both qubits. We generalize a recently introduced method which does not require the detection of both qubits, by extending it to cover a wider class of entangled states. Specifically, we present a detailed theory that shows how to measure entanglement in a family of two-qubit mixed states - obtained by generalizing Werner states - without detecting one of the qubits. Our method is interferometric and does not require any coincidence measurement or postselection. We also perform a quantitative analysis of anticipated experimental imperfections to show that the method is experimentally implementable and resistant to experimental losses.

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Salini Rajeev, Mayukh Lahiri. 2023-06-07. Single-qubit measurement of two-qubit entanglement in generalized Werner states. https://doi.org/10.1103/physreva.108.052410

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