Polaritonic spectroscopy of intersubband transitions

TL;DR

This study investigates intersubband excitations in quantum wells coupled with microcavities in the THz range, combining experimental data with quantum and electromagnetic modeling to understand light-matter interactions and electronic populations.

Contribution

It introduces a combined quantum and electromagnetic modeling approach for intersubband systems, enabling detailed analysis and design of light-matter interactions in microcavities.

Findings

Successful modeling of intersubband excitations with loss considerations

Retrieval of electronic populations as a function of temperature

Establishment of a predictive tool for designing intersubband light-matter systems

Abstract

We report on an extensive experimental study of intersubband excitations in the THz range arising from the coupling between a quantum well and a zero-dimensional metal-metal microcavities. Because of the conceptual simplicity of the resonators we obtain an extremely predictable and controllable system to investigate light-matter interaction. The experimental data is modelled by combining a quantum mechanical approach with an effective medium electromagnetic simulation that allows us to take into account the losses of the system. By comparing our modelling with the data we are able to retrieve microscopic information, such as the electronic populations on different subbands as a function of the temperature. Our modelling approach sets the base of a designer tool for intersubband light-matter coupled systems.