Novel Polaron State for Single Impurity in a Bosonic Mott Insulator

TL;DR

This paper introduces a new type of polaron formed by a single impurity in a bosonic Mott insulator, showing tunable properties and a critical transition to deconfined states, relevant for cold atom experiments.

Contribution

It reveals a novel polaron state with diverging effective mass and size, and demonstrates controllable transition to deconfined impurity-hole and boson particle states.

Findings

Polaron exhibits correlated motion with diverging effective mass.

Polaron size nearly diverges at a critical interaction strength.

Transition to deconfined impurity-hole and boson particle states is controllable.

Abstract

We show that a single impurity embedded in a cold atom bosonic Mott insulator leads to a novel polaron that exhibits correlated motion with an effective mass and a linear size that nearly diverge at critical value of the on-site impurity-boson interaction strength. Cold atom technology can tune the polaron's properties and break up the composite particle into a deconfined impurity-hole and boson particle state at finite, controllable polaron momentum.