Polaritonic Tamm states induced by cavity photons

TL;DR

This paper demonstrates that strong light-matter coupling in a cavity can induce localized polaritonic Tamm states at the ends of a dipolar chain, with localization properties depending on cavity size.

Contribution

It introduces the concept of polaritonic Tamm states in a dipolar chain within a cavity, highlighting the role of cavity size in state localization.

Findings

Localized Tamm states appear at the chain ends due to polariton formation.

Cavity size above a critical threshold is necessary for Tamm state formation.

Participation ratio of Tamm states scales linearly with cavity cross-sectional area.

Abstract

We consider a periodic chain of oscillating dipoles, interacting via long-range dipole-dipole interactions, embedded inside a cuboid cavity waveguide. We show that the mixing between the dipolar excitations and cavity photons into polaritons can lead to the appearance of new states localized at the ends of the dipolar chain, which are reminiscent of Tamm surface states found in electronic systems. A crucial requirement for the formation of polaritonic Tamm states is that the cavity cross-section is above a critical size. Above this threshold, the degree of localization of the Tamm states is highly dependent on the cavity size, since their participation ratio scales linearly with the cavity cross-sectional area. Our findings may be important for quantum confinement effects in one-dimensional systems with strong light-matter coupling.