# Protecting quantum correlations in presence of generalised amplitude damping channel: the two-qubit case

## TL;DR

This paper investigates how quantum correlations like entanglement and steering in two-qubit systems are affected by the generalized amplitude damping channel and proposes protocols using weak measurement and POVMs to preserve these correlations.

## Contribution

It introduces protocols employing weak measurement and POVMs to effectively preserve quantum correlations under generalized amplitude damping noise.

## Key findings

- Weak measurement and reversal can preserve correlations.
- Evolution under the channel can be viewed as a unitary process.
- Protocols work over a large parameter range.

## Abstract

Any kind of quantum resource useful in different information processing tasks is vulnerable to several types of environmental noise. Here we study the behaviour of quantum correlations such as entanglement and steering in two-qubit systems under the application of the generalised amplitude damping channel and propose some protocols towards preserving them under this type of noise. First, we employ the technique of weak measurement and reversal for the purpose of preservation of correlations. We then show how the evolution under the channel action can be seen as an unitary process. We use the technique of weak measurement and most general form of selective positive operator valued measure (POVM) to achieve preservation of correlations for a significantly large range of parameter values.