# Entanglement concentration with different measurement in a 3-mode optomechanical system

## TL;DR

This paper investigates how different phonon counting measurements in a 3-mode optomechanical system affect entanglement, showing that more precise measurements lead to greater entanglement enhancement.

## Contribution

It compares the effects of imperfect, perfect, and on-off measurements on entanglement concentration in a 3-mode optomechanical system.

## Key findings

- Perfect measurement yields the largest entanglement increase.
- Imperfect measurement also enhances entanglement, but less than perfect.
- On-off measurement shows less clear entanglement enhancement.

## Abstract

In this work, we perform a series of phonon counting measurement with different methods in a 3-mode optomechanical system, and we compare the difference of the entanglement after measurement. In this article we focus on the two cases: imperfect measurement and on-off measurement. We find that whatever measurement you take, the entanglement will increase. The size of entanglement enhancement is the largest in perfect measurement, second in the imperfect measurement, and it is not obvious in the on-off measurement. We are sure that the more precise measurement information, the larger entanglement concentration.