Absorptive and dispersive optical responses of excitons in a single quantum dot

TL;DR

This paper investigates the optical responses of excitons in a single quantum dot by measuring the dielectric polarizability through interference effects in Rayleigh scattering near resonance.

Contribution

It presents a novel experimental method to determine both real and imaginary parts of dielectric polarizability of individual quantum dots using interference in Rayleigh scattering.

Findings

Measured dielectric polarizability of single quantum dots.

Demonstrated control of scattering via interference effects.

Provided insights into excitonic optical properties at the single-dot level.

Abstract

We have determined both the real and imaginary parts of the dielectric polarizability of a single quantum dot. The experiment is based on the observation and the manipulation of Rayleigh scattering at photon frequencies near the resonance of an optical exciton transition in single self-assembled InAs and InGaAs quantum dots. The interference between the narrow-band laser field and the weak electromagnetic field coherently scattered by the quantum dot is detected with a cryogenic Fabry-Perot setup by combined differential transmission and reflectivity measurements.