Controlling dynamical entanglement in a Josephson tunneling junction

TL;DR

This paper investigates how many-body interactions influence the formation and control of entangled states, specifically N00N states, in a Josephson tunneling junction, highlighting the role of interaction strength and time scale.

Contribution

It demonstrates that moderate interactions enable the formation of N00N states within a specific time window inversely related to tunneling rate, revealing how interactions support entanglement.

Findings

N00N states appear with sufficient probability only for moderate interactions.

The relevant time scale for entanglement is inversely proportional to tunneling rate.

Interaction enhances entanglement, reducing decay rate of entangled state probability.

Abstract

We analyze the evolution of an entangled many-body state in a Josephson tunneling junction. A N00N state, which is a superposition of two complementary Fock states, appears in the evolution with sufficient probability only for a moderate many-body interaction on an intermediate time scale. This time scale is inversely proportional to the tunneling rate. Interaction between particles supports entanglement: The probability for creating an entangled state decays exponentially with the number of non-interacting particles, whereas it decays only like the inverse square root of the number of interacting particles.