# Decoherence induced spin squeezing signatures in Greenberger-Horne-Zeilinger and W states

## TL;DR

This paper investigates how various decoherence channels can induce spin squeezing in entangled GHZ and W states, revealing that decoherence can have a constructive role in generating spin squeezing rather than solely destroying it.

## Contribution

It is the first study to show that decoherence can produce spin squeezing in initially unsqueezed GHZ and W states, highlighting positive effects of decoherence on quantum correlations.

## Key findings

- GHZ states remain unsqueezed under most channels except specific ones.
- All channels induce spin squeezing in W states.
- No spin squeezing sudden death observed in either state.

## Abstract

We reckon the behaviour of spin squeezing in tripartite unsqueezed maximally entangled Green- berger-Horne-Zeilinger (GHZ) and W states under various decoherence channels with Kitagawa- Ueda (KU) criteria. In order to search spin squeezing sudden death (SSSD) and signatures of spin squeezing production we use bit flip, phase flip, bit-phase-flip, amplitude damping, phase damping and depolarization channels in the present study. In literature, the influence of decoherence has been studied as a destroying element. On the contrary here we investigate the positive aspect of decoherence, which produce spin squeezing in unsqueezed GHZ and W states under certain channels. Our meticulous study shows that GHZ state remain unsqueezed under aforementioned channels except bit-phase-flip and depolarization channels. While all the decoherence channels produce spin squeezing in W state. So we find, GHZ is more robust in comparison to W state in the sense of spin squeezing production under decoherence. Most importantly we find that none of the decoherence channel produce SSSD in any one of the state.