Circular-polarization sensitive metamaterial based on triple quantum-dot molecules

TL;DR

This paper introduces a novel chiral metamaterial using triple quantum-dot molecules that can be controlled via magnetic fields to manipulate circular polarization, birefringence, and lasing properties.

Contribution

It presents a new design of a chiral metamaterial based on quantum-dot molecules with tunable polarization and emission characteristics under magnetic fields.

Findings

Strong birefringence above threshold frequency {8}

Ability to achieve Kerr rotation and circularly polarized lasing

Robustness against stray electric fields and geometric deviations

Abstract

We propose a new type of a chiral metamaterial based on an ensemble of artificial molecules formed by three identical quantum-dots in a triangular arrangement. A static magnetic field oriented perpendicular to the plane breaks mirror symmetry, rendering the molecules sensitive to the circular polarization of light. By varying the orientation and magnitude of the magnetic field one can control the polarization and frequency of the emission spectrum. We identify a threshold frequency, {\Omega}, above which we find strong birefringence. In addition, a Kerr rotation and circularly polarized lasing action can be implemented. We investigate the single-molecule lasing properties for different energy-level arrangements and demonstrate the possibility of circular polarization conversion. Finally, we analyze the effect of weak stray electric fields or deviations from the equilateral triangular geometry.