Entanglement between a Two-level System and a Quantum Harmonic Oscillator

TL;DR

This paper investigates how entanglement between a two-level system and a quantum harmonic oscillator can be enhanced or dissipated through interactions, pulse sequences, and environmental effects, revealing complex dynamics and parameter-dependent behaviors.

Contribution

It introduces a detailed analysis of entanglement dynamics under pulse sequences and decoherence, highlighting conditions for maximum entanglement and its dissipation over time.

Findings

Maximum entanglement achievable without decoherence.

Entanglement dissipates to thermal equilibrium with bath.

Discontinuous jumps in entanglement timing based on decoherence parameters.

Abstract

The entanglement between a Pauli-like two-level system and a quantum harmonic oscillator enhanced by an interaction between them and a $\delta$-pulse sequence is studied, with the decoherence due to their coupling with a Markovian bath. Without the Markovian bath, the entanglement is enhanced to maximum possible values. With the Markovian bath, the entanglement is enhanced up to some time and then dissipated, with the system in thermal equilibrium with the Markovian bath after a very long time. The time for achieving the maximum entanglement shows discontinuous jumps over the parameters of decoherence.