Non-Hermitian approach for quantum plasmonics

TL;DR

This paper explores a simplified non-Hermitian model for exciton/plasmon interactions in quantum plasmonics, highlighting its applicability, limitations, and extensions to many quantum dots, offering a computationally efficient alternative to traditional methods.

Contribution

It introduces and evaluates a non-Hermitian model as a simpler alternative to Lindblad approaches for quantum plasmonics, including extensions to multiple quantum dots.

Findings

Optical spectra are well described by the model in the linear regime.

The model can qualitatively describe coherences and entanglement with dissipation and dephasing.

Results for fifty quantum dots interacting with a plasmon are presented within the single-excitation manifold.

Abstract

We examine the limits of applicability of a simple non-Hermitian model for exciton/plasmon interactions in the presence of dissipation and dephasing. The model can be used as an alternative to the more complete Lindblad density matrix approach and is computationally and conceptually simpler. We find that optical spectra in the linear regime can be adequately described by this approach. The model can fail, however, under continuous optical driving in some circumstances. In the case of two quantum dots or excitons interacting with a plasmon, the model can also describe coherences and entanglement qualitatively when both dissipation and dephasing are present, and quantitatively in the limit with no dephasing. The model can also be extended to the case of many quantum dots interacting with a plasmon and results, within the single-excitation manifold, are presented for the fifty quantum dot case.