Modulation of entanglement between two oscillators separated in space with an optical parametric amplifier

TL;DR

This paper presents a scheme to control entanglement between two spatially separated oscillators using an optical parametric amplifier, highlighting the role of Coulomb interaction and the modulation of cavity field squeezing.

Contribution

The scheme introduces modulation of entanglement via an optical parametric amplifier and Coulomb interaction, offering enhanced robustness over previous methods.

Findings

Entanglement is primarily due to Coulomb interaction.

Optical parametric amplifier gain and pump phase modulate the cavity field.

The scheme shows improved robustness against environmental temperature.

Abstract

We propose a scheme to modulate the entanglement between two oscillators separated in space via the squeezing cavity field generated by the optical parametric amplifier instead of injecting the squeezing field directly with the assistance of Coulomb interaction. We show that the Coulomb interaction between the oscillators is the essential reason for the existence of entanglement. Due to the gain of the optical parametric amplifier and the phase of the pump driving the optical parametric amplifier can simultaneously modulate the squeezing cavity field, the radiation pressure interaction between the cavity field and the oscillator is modulated accordingly. We find that there is competing effect between the radiation pressure interaction and the Coulomb interaction for the oscillator which these two interactions act on simultaneously. Therefore, the modulation of entanglement can be achieved with the assistance of Coulomb interaction. The results of numerical simulation show that the present scheme has stronger robustness against the temperature of environment compared with previous schemes in experimentally feasible regimes.