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arXiv · 2008.12971

Generating and detecting bound entanglement in two-qutrits using a family of indecomposable positive maps

Bihalan Bhattacharya·Suchetana Goswami·Rounak Mundra·Nirman Ganguly·Indranil Chakrabarty·Samyadeb Bhattacharya·A. S. Majumdar
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Abstract

The problem of bound entanglement detection is a challenging aspect of quantum information theory for higher dimensional systems. Here, we propose an indecomposable positive map for two-qutrit systems, which is shown to generate a class of positive partial transposed (PPT) states. A corresponding witness operator is constructed and shown to be weakly optimal and locally implementable. Further, we perform a structural physical approximation of the indecomposable map to make it a completely positive one, and find a new PPT entangled state which is not detectable by certain other well-known entanglement detection criteria.

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Bihalan Bhattacharya, Suchetana Goswami, Rounak Mundra, Nirman Ganguly, Indranil Chakrabarty, Samyadeb Bhattacharya, A. S. Majumdar. 2020-08-29. Generating and detecting bound entanglement in two-qutrits using a family of indecomposable positive maps. https://doi.org/10.1088/2399-6528%2Fac0b01

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