Conditional Entanglement Amplification via Non-Hermitian Superradiant Dynamics

TL;DR

This paper demonstrates a method to significantly increase the probability of generating highly entangled quantum states, such as cat states, in atomic ensembles undergoing superradiant decay by using non-Hermitian dynamics and non-classical initial states.

Contribution

It introduces a novel approach to amplify the likelihood of creating highly entangled states in dissipative quantum systems through non-Hermitian superradiant dynamics and specific initial state preparation.

Findings

Maximized probability of entangled state generation using non-Hermitian Hamiltonian analysis.

Identified non-classical initial states as essential for entanglement amplification.

Showed potential for creating maximally entangled cat states in cavity-QED systems.

Abstract

Due to the inherently probabilistic nature of quantum mechanics, each experimental realization of a dynamical quantum system may yield a different measurement outcome, especially when the system is coupled to an environment that causes dissipation. Although it is in principle possible that some quantum trajectories lead to exotic highly entangled quantum states, the probability of observing these trajectories is usually extremely low. In this work, we show how to maximize the probability of generating highly entangled states, including maximally entangled cat states, in an ensemble of atoms experiencing superradiant decay. To this end, we analyze an effective non-Hermitian Hamiltonian which governs the dynamics between the quantum jumps associated with photon emission. A key result of our study is that, in order to maximally enhance the probability of cat state generation, the initial state needs to be non-classical. This can be achieved e.g. with one-axis twisting in a cavity-QED system.