Welcome to JJEM: A Multi-Disicplinary Journal of JNNCE, Shimoga

JJEM Thirteenth Issue - Volume 7 Number 1 -2022

Volume 7, Issue 1

Conditional Sandwiched Rényi Relative Entropy and its application in separability of single parameter families of 3, 4 qubit W and GHZ density functions

Published:    2023-08-10


Anantha S. Nayak


An increase in activity has been seen recently in the study of entanglement in bipartite quantum systems. The entropic characterization of separability of composite quantum systems has attracted a lot of interest among diverse techniques. In this research article, a new form of conditional Rényi relative entropy (known as Conditional Sandwiched Rényi Relative Entropy (CSRRE) form) is used to determine the bipartite separability limit in single parameter families of mixed W- and GHZ- states. For N=3, 4 qubits, the non-entanglement limit in the 1: N-1 partition of these states determined using CSRRE criterion is more restrictive than the separability range discovered by Abe-Rajagopal’s form of Tsallis entropy. It's established that1: N-1separabilty range determined using CSRRE approach precisely with the range determined by positivity of partial transpose criterion.


: Entanglement, Rényi relative entropy, Mixed W- and GHZ- states, Positivity of partial transpose